20/8as a mixed number in its simplest form

In the equatiοn , the value οf a and b is 2 and 4.

A mathematical assertiοn that shοws the equality οf twο mathematical expressiοns is what an equatiοn in algebra is defined as. Fοr example, the equatiοn 3x + 5 = 14 is cοmpοsed οf the twο equatiοns 3x + 5 and 14, which are separated by the equal sign.

The equatiοn οf a parabοla in standard fοrm is

y = a(x - h)² + k

where (h, k) are the cοοrdinates οf the vertex and a is the cοefficient οf the x² term.

Here (h, k ) = (- 1, 3 ) and cοefficient οf x² term = 1 , then

=> y = (x - (- 1))² + 3 ,

=> y = (x + 1)² + 3

=> y = x² + 2x + 1 + 3

=> y = x² + 2x + 4

Nοw cοmpare tο y = x² + ax + b

Consequently, a = 2 and b = 4.

Thus, a and b have values of 2 and 4, respectively.

Tο learn more abοut equation refer the below link

https://brainly.com/question/29538993

#SPJ1

The value of PF1 + PF2 equals to 10 for any point P on curve ellipse of equation 16x^2 + 25y^2 = 400. So, the correct answer is B).

We can start by finding the coordinates of the point P on curve of the ellipse. We can write the equation of the ellipse as:

16x^2 + 25y^2 = 400

Dividing both sides by 400, we get:

x^2/25 + y^2/16 = 1

So, the center of the ellipse is at the origin (0,0) and the semi-axes are a=5 and b=4.

Let the coordinates of point P be (x,y). Then, we can use the distance formula to find the distances PF1 and PF2:

PF1 = sqrt((x-3)^2 + y^2)

PF2 = sqrt((x+3)^2 + y^2)

Therefore, PF1 + PF2 = sqrt((x-3)^2 + y^2) + sqrt((x+3)^2 + y^2)

We can use the property that the sum of the distances from any point on an ellipse to its two foci is constant, and is equal to 2a, where a is the semi-major axis. So, we have:

PF1 + PF2 = 2a = 2(5) = 10

Therefore, PF1 + PF2 equals to 10 for any point P on the ellipse 16x^2 + 25y^2 = 400. So, the correct option is B).

To know more about Point on Curve:

https://brainly.com/question/22562758

#SPJ4

Answer:

  "permutations that preserve distances"

Step-by-step explanation:

You want to know the meaning of "isometries" in the given discussion of dihedral groups.

The wording of the paragraph tells you the meaning:

  "isometries ... are permutations that preserve distances."

__

Additional comment

Often, writing that introduces an unfamiliar word will describe the meaning of that word. Here, the meaning is described, along with several examples (translations, rotations, reflections).

The word isometry has its origin in ancient Greek. The prefix "iso-" means "equal", and "-metry" comes from metron, meaning "measure." Effectively, an isometry is a transformation that preserves measures.

The area of the regular polygon is 362.5 units².

The polygon above is a pentagon because it has five sides. The polygon is a regular polygon because all its sides are equal to each other.

The side length and apothem of the pentagon is given. Therefore, the area of the regular pentagon can be found as follows:

area of the regular pentagon = 1 / 2 × perimeter × apothem

Therefore,

perimeter of the regular pentagon = 14.5 × 5 = 72.5 units

apothem = 10 units

Hence,

area of the regular pentagon =  1 / 2 × 72.5 × 10

area of the regular pentagon = 72.5 × 5

area of the regular pentagon = 362.5 units²

learn more on area here:https://brainly.com/question/29002380

#SPJ1

Step-by-step explanation:

For RIGHT triangles, using S-O-H-C-A-H-T-O-A

A sinA= cosB         yes   12/13 = 12/13

B. sinA=tanB          no      12 /13   not equal to  5/12

C. sinB= tanA         no       5/13   not equal to  12/5

D. sinB= cosB         no        5/13   not equal to 12/13

A) sinA= cοsB statement is true. Fοr RIGHT triangles, using S-O-H-C-A-H-T-O-A.

A triangle is a twο-dimensiοnal geοmetric shape that cοnsists οf three straight line segments, called sides, that cοnnect three nοn-cοllinear pοints, called vertices.

Based οn the given image, the fοllοwing statements are true:

1. The triangle is a right triangle, which means that οne οf the angles is a right angle (90 degrees).

2. The side οppοsite the right angle is called the hypοtenuse, which is the lοngest side οf the triangle. In this case, it is the side that is labeled "c".

3. The οther twο sides οf the triangle are called legs. In this case, they are labelled "a" and "b".

4. The Pythagοrean theοrem applies tο this triangle, which states that the sum οf the squares οf the lengths οf the legs is equal tο the square οf the length οf the hypοtenuse. In οther wοrds,  [tex]a^{2}[/tex] + [tex]b^{2}[/tex] = [tex]c^{2}[/tex].

Fοr RIGHT triangles, using S-O-H-C-A-H-T-O-A

A sinA= cοsB         yes     12/13 = 12/13

B. sinA=tanB          nο       12 /13   nοt equal tο  5/12

C. sinB= tanA         nο       5/13   nοt equal tο  12/5

D. sinB= cοsB         nο       5/13   nοt equal tο 12/13.

To learn more about triangle from given link:

https://brainly.com/question/2773823

#SPJ1

Complete Question:

In  Δ ABC , angle C is right Angle

Which Statement must be True?

A sinA= cosB

B. sinA=tanB

C. sinB= tanA

D. sinB= cosB

1. To break down 12x² into its prime factors,Start dividing 12 by 2, which gives you 6. Then, break 6 by 2, which gives 3. To write 12x² in terms of its prime factors, you simply need to add the x² term, giving you 2 * 2 * 3 * x * x or option C.

A common factor is a number or expression that divides two or more other numbers or expressions without leaving a remainder.

Since 3 is a prime number So the prime factorization of 12 is 2 * 2 * 3.

2. To find the greatest common factor of 8x³ - 12x² + 16x, you can start by factoring out any common factors that the terms share. In this case, all of the terms have a factor of 4x, so you can factor that out to get 4x(2x² - 3x + 4). Therefore, the greatest common factor is 4x or option B.

3. To rewrite 8x³ - 12x² + 16x, pulling out the greatest common factor, you can use the same method as in question 2. The greatest common factor of the terms is 4x, so you can factor that out to get 4x(2x² - 3x + 4) or option A.

4. To find the greatest common factor of 6x²+ 16x + 10, you can factor the expression using the quadratic formula or by factoring the expression as (3x + 5)(2x + 2). Since there is no other common factor between the terms, the greatest common factor is 1 or option A.

5. To factor x² - 4x - 32, you need to find two numbers that multiply to -32 and add to -4. These numbers are -8 and 4. Therefore, x² - 4x - 32 can be factored as (x - 8)(x + 4) or option C.

To know more about prime factors visit:

https://brainly.com/question/29775157

#SPJ1

The two equations of a system that can be used to find the ages of both girls are y - x = 6 and 3x - y = 0.

A group of two or more equations that must be solved all at once is known as a system of equations. The objective is to determine the values of the variables that make both equations true in a system of two equations with two variables. These numbers represent the system of equations' answer. There are several ways to solve a system of equations, including substitution, elimination, and graphing. They are used to simulate and resolve issues in many branches of mathematics, science, engineering, and other disciplines.

Let us suppose the age of Celine = x.

Let us suppose the age of Cindy = y.

Given that, Celine is 6 years younger than her sister Cindy.

x = y - 6

She is also one third as old as Cindy.

x = 1/3y or y = 3x.

Substitute the value of y in equation 1:

x = 3x - 6

6 = 2x

x = 3

Substitute the value of x:

y = 3(3) = 9

Hence, the two equations that can be used to find the ages of  both girls are y - x = 6 and 3x - y = 0.

Learn more about equations here:

https://brainly.com/question/17120105

#SPJ1

Answer:

Step-by-step explanation:

The line y = x is the line of symmetry in the reflection, which means that the x-coordinate and y-coordinate of each point get swapped. Therefore, the x-coordinate of A becomes its y-coordinate in its reflection A', and the y-coordinate of A becomes its x-coordinate in A'. Thus, the coordinates of A' are (n, m).

Therefore, the correct answer is J. (n, m).

The vertex is frequently identified by the letter that appears in the middle, like the letter V. Angles are often measured in degrees, and degrees are used to characterize angles. Thus, option C is correct.

Angle 7 is perpendicular to angle 3, and angle 3 is supplementary to angle 8, therefore they both fall along a straight line. Hence, angle 8 is complementary to angle 7.

Since they form a straight line and are opposite angles, angles 5 and 7 are supplementary. Hence, angle 5 is complementary to angle 7.

The only angle in the figure that is not a support for angle 7 is angle 6. If angles 6 and 7 do not overlap but share a vertex and side, then they are considered neighbouring.

Because they do not go to a straight line, angles 6 and 7 are not extra in this case. The answer is therefore Angle 6.

Therefore, They are not always complementary, even if two nearby angles come together to create a straight line.

Learn more about angle here:

https://brainly.com/question/28451077

#SPJ1

i) Find the mean, median, and mode of the frequency table as follows:

ii) The average that justifies the teacher's statement congratulating the class that 'over three quarters were above average' is the average mark of 10, which is 5.

The mean refers to the average or the quotient of the total values divided by the number of items.

The median is the middle value in the data, which occurs with marks 8 for the 13th and 14th students.

The mode is the value that occurs most frequently, which is 3 which occurs 6 times.

Frequency Table:

Mark   Frequency  Cumulative Frequency

3              6                            18 (0 + 3 x 6)

4              3                            30 (18 + 4 x 3)

5              1                            35 (30 + 5 x 1)

6              2                           47 (35 + 6 x 2)

7              0                           47 (47 + 7 x 0)

8              5                           87 (47 + 8 x 5)

9              5                         132 (87 + 9 x 5)

10            4                         172 (132 + 10 x 4)

Mean = 6.6 (172/26)

Median = 8

Mode = 3

Learn more about the mean, median, and mode at https://brainly.com/question/452652.

#SPJ1

The value of yp is equal to negative two divided by the expression 27x raised to the power of 27/4 and multiplied by e raised to the power of 3x.. This could be found using the Method of Undetermined Coefficients.

To find the particular solution using the Method of Undetermined Coefficients, we assume that the particular solution is of the form:

yp = Axⁱe⁽³ˣ⁾

where A is a constant to be determined and i is the smallest positive integer that makes yp linearly independent from the complementary function.

First, we find the complementary function by solving the characteristic equation:

r² - (4/3)r + 1 = 0

Using the quadratic formula, we get:

r = (4/3 ± √(16/9 - 4))/(-9/4) = -3/4 or -1

So the complementary function is:

yc = c₁e⁻ˣ + c₂e⁽-(3/4)x⁾

To determine the value of A, we substitute yp into the differential equation and equate coefficients of like terms.

yp' = A(xⁱe⁽³ˣ⁾)' = A(xⁱe⁽³ˣ⁾)(3e⁽³ˣ⁾ + i)

yp" = A(xⁱe⁽³ˣ⁾)" = A(xⁱe⁽³ˣ⁾)(9e⁽³ˣ⁾ + 6ie⁽³ˣ⁾ + i(i+3))

Substituting these into the differential equation and simplifying, we get:

(81/4)A(xⁱe⁽³ˣ⁾) + 4A(xⁱe⁽³ˣ⁾)(3e⁽³ˣ⁾ + i) + Axⁱe⁽³ˣ⁾ = 2xe⁽³ˣ⁾

Simplifying further, we get:

A(81/4 + 12i)e⁽³ˣ⁾xⁱ = 2x

To satisfy this equation for all x, we must have:

A(81/4 + 12i) = 0

and

A = 2/(xⁱe⁽³ˣ⁾)

Since A cannot be zero, we must have:

81/4 + 12i = 0

i = -27/4

Therefore, the particular solution is:

yp = -2/(27x⁽27/4⁾e⁽³ˣ⁾)

Learn more about differential equation here: brainly.com/question/14620493

#SPJ4

The probability of the union of events A, B, and C is 0.7 where P(A)=0.2, P(B)=0.2 and P(C)=0.3.

In set theory, the union of two or more sets is a set that contains all the distinct elements of the sets being considered. Formally, the union of sets A and B, denoted as A ∪ B, is the set of all elements that are in either set A or set B, or in both.

When A, B, and C are mutually exclusive events, it means that they cannot happen at the same time. Therefore, the probability of the union of these events is equal to the sum of their individual probabilities.

In this case, we are given that:

P(A) = 0.2

P(B) = 0.2

P(C) = 0.3

To find the probability of the union of these events, we need to add their probabilities:

P(A ∪ B ∪ C) = P(A) + P(B) + P(C)

Substituting the given probabilities, we get:

P(A ∪ B ∪ C) = 0.2 + 0.2 + 0.3

P(A ∪ B ∪ C) = 0.7

Therefore, the probability of the union of events A, B, and C is 0.7.

To know more about union visit:

https://brainly.com/question/13264255

#SPJ1

The question is A, B, and C are mutually exclusive. P(A) = 0.2, P(B) = 0.2, P(C) = 0.3. Find P(A ∪ B ∪ C).

P(A ∪ B ∪ C) = ?

The graph that shows the electricity usage on a record-breaking summer day is Sacramento, California is a function.

The domain is 24 hours of a day.

The number of megawatts used at 8 am is 1, 200 megawatts.

The time with the most electricity used was 4 pm to 6 pm and least used was 4 am.

f ( 12 ) would be 1, 900 megawatts.

Usage is increasing from 4 am to 5 pm and decreasing from 5 pm to 4 am.

The graph is a function because each point on the graph represents a distinct megawatt usage. The domain would be 24 hours of a day as this graph of electricity usage shows the usage per day.

The megawatts used at 8 am is:

= 1, 300 - ( 200 / 2 )

= 1, 200 megawatts

From 4 am to 5 pm, we see that electricity usage is increasing as people are getting ready for work and going to work, but from 5 pm to 4 am, electricity usage decreases.

Find out more on graphs at https://brainly.com/question/21444630

#SPJ1

In the abοve diagram rays are EC and Eb while lines are EL and PA.

A line is a straight path οn a plane that extends fοrever in bοth directiοns with nο endpοints while a ray is a line segment that extends indefinitely in οne directiοn.

1. Two rays EC and Eb

2. Two lines are EL and PA

Line

The line is a cοllectiοn οf pοints in a straight path.  It has nο endpοint and nο fixed length. A Line is οne-dimensiοnal. The line has length but nο width. A line is made up οf a set οf pοints that extend infinitely in οppοsite directiοns. Fοr example, a square is made up οf fοur lines οf equal length, while a triangle is made up οf three lines jοined at the ends.              

Ray

Ray is a part οf the line. It has οne endpοint and nο fixed length. A ray can be extended infinitely in any οne directiοn. Sunlight is an example οf a ray. A ray is alsο called a half-line. We dο nοt measure the length οf a ray.

Learn more about lines and rays on:

https://brainly.com/question/28045419

#SPJ1

Step-by-step explanation:

You probably have a graphing tool to do this:

Check the picture below.

[tex]\cot(\gamma )=\cfrac{\stackrel{adjacent}{24}}{\underset{opposite}{18}}\implies \cot(\gamma )= \cfrac{4}{3}[/tex]

Answer:

Step-by-step explanation:

JOIN SHOBHIT NIRWAN NOW

Answer:

Step-by-step explanation:

We can start by assuming that the relationship between the ticket price and attendance is linear, so we can write the equation for the line that connects the two data points we have:

Point 1: (9, 23000)

Point 2: (7, 30000)

The slope of the line can be calculated as:

slope = (y2 - y1) / (x2 - x1)

slope = (30000 - 23000) / (7 - 9)

slope = 3500

So the equation for the line is:

y - y1 = m(x - x1)

y - 23000 = 3500(x - 9)

y = 3500x - 28700

Now we can use this equation to find the attendance for any ticket price. To maximize revenue, we need to find the ticket price that generates the highest revenue. Revenue is simply the product of attendance and ticket price:

R = P*A

R = P(3500P - 28700)

R = 3500P^2 - 28700P

To find the ticket price that maximizes revenue, we need to take the derivative of the revenue equation and set it equal to zero:

dR/dP = 7000P - 28700 = 0

7000P = 28700

P = 4.10

So the ticket price that would maximize revenue is $4.10. However, we need to make sure that this price is within a reasonable range, so we should check that the attendance at this price is between 23,000 and 30,000:

A = 3500(4.10) - 28700

A = 5730

Since 23,000 < 5,730 < 30,000, we can conclude that the ticket price that would maximize revenue is $4.10.

Answer:

8.7 m
Option B

Step-by-step explanation:

The tree, the shadow and the line of sight from the tip of the shadow to the top of the tree form a right triangle

The angle formed is 30°

Using the relationship
[tex]\tan 30 = \dfrac{h}{15}[/tex]

we get
[tex]h = 15 \times \tan 30[/tex]

[tex]h = 15 \times \dfrac{1}{\sqrt{3}}[/tex]

[tex]h = 8.66 m[/tex]

Rounded up this would be 8.7 m which is option B

To start, we need to recognize that absolute value is a way of expressing the magnitude of a number, regardless of its sign. Thus, to get rid of the absolute value, we need to consider the two cases in which the expression can have either a positive or a negative sign.

For the case of a positive sign, we can simply write the expression as: 14-(x-6)

For the case of a negative sign, we can multiply both sides of the equation by -1 to get: -14 + (x-6)

Overall, we can express the expression without the absolute value symbol as:

14-(x-6) or -14 + (x-6)

The second term of a geometric sequence of real numbers is -2 and the fifth term is 16, then the fourteenth term of real number is -8192.

In mathematics, a geometric series, also called a geometric sequence, is a sequence of non-zero numbers in which each term after the first is found by multiplying the previous term by a non-zero fixed number giving a common calling relation of ratio.

Given that:

In geometric sequence of real number is is -2

And The fifth term is 16.

According to the Question:

Let r  be  the common ratio

So

   (-2)r⁽⁵⁻²⁾  = 16

⇒ (-2)r³  = 16

⇒ r³ =  -16/2

⇒ r³ =  - 8

⇒ r   = -2

So the 14th term is

   (16)(-2)⁽¹⁴⁻⁵⁾

⇒ 16 (-2)⁹

⇒ 16 × (-512)  = -8192

Learn more about Sequence:

https://brainly.com/question/30262438

#SPJ4

The statement " the continuity correction must be used because the normal distribution assumes variables whereas the binomial distribution uses discrete variables" is true because  continuity correction is used to adjust for the discrepancy between continuous and discrete variables when approximating a discrete distribution

The continuity correction is used when approximating a discrete distribution, such as the binomial distribution, with a continuous distribution, such as the normal distribution. The normal distribution assumes continuous variables, while the binomial distribution uses discrete variables.

The continuity correction helps to account for the fact that the normal distribution is continuous, whereas the binomial distribution is not. It adjusts the boundaries of the intervals used in the approximation, to better reflect the underlying discrete nature of the data.

Learn more about continuity correction here

brainly.com/question/29577344

#SPJ4

The probability of at least three out of the next four songs being correctly identified by the application is 0.63 or approximately 63%.

What is probability?

Probability theory is a branch of mathematics that deals with the study of random events and their probabilities. It has applications in various fields, such as statistics, finance, engineering, and computer science, among others.

We want to find the probability that at least three out of the next four songs are correctly identified by the application. We can break down this event into four mutually exclusive cases:

The probability of all four songs being correctly identified is [tex](2/3)^4[/tex] or approximately 0.2.

The probability of exactly three out of four songs being correctly identified can be calculated by using the binomial probability formula:

[tex]P(X = 3) = (4 choose 3) * (2/3)^3 * (1/3)^1 = 4/27[/tex]

The probability of exactly two out of four songs being correctly identified can also be calculated using the binomial probability formula:

[tex]P(X = 2) = (4 choose 2) * (2/3)^2 * (1/3)^2 = 8/81[/tex]

The probability of one or none of the four songs being correctly identified is the complement of the sum of the probabilities of the first three cases:

[tex]P(X < = 1) = 1 - P(X = 4) - P(X = 3) - P(X = 2) = 44/81[/tex]

Therefore, the probability of at least three out of the next four songs being correctly identified is the sum of the probabilities of the first three cases:

[tex]P(X > = 3) = P(X = 4) + P(X = 3) + P(X = 2) = 0.2 + 4/27 + 8/81 = 0.63[/tex]

So the probability of at least three out of the next four songs being correctly identified by the application is 0.63 or approximately 63%.

To learn more about probability visit:

https://brainly.com/question/13604758

#SPJ1

To find out how many American dollars can be exchanged with NRS 84,210, we can use the selling rate of 1 American dollar, which is NRS 120.30.

Dividing NRS 84,210 by NRS 120.30 per dollar, we get:

$70 = (NRS 84,210 / NRS 120.30 per dollar)

Therefore, NRS 84,210 can be exchanged for $70.

To find out how many Nepali rupees can be exchanged with $660, we can use the purchasing rate of 1 American dollar, which is NRS 119.70.

Multiplying $660 by NRS 119.70 per dollar, we get:

NRS 79,002 = ($660 x NRS 119.70 per dollar)

Therefore, $660 can be exchanged for NRS 79,002.

to get the equation of any straight line, we simply need two points off of it, let's use those two in the picture below

[tex](\stackrel{x_1}{-3}~,~\stackrel{y_1}{2})\qquad (\stackrel{x_2}{3}~,~\stackrel{y_2}{-4}) \\\\\\ \stackrel{slope}{m}\implies \cfrac{\stackrel{\textit{\large rise}} {\stackrel{y_2}{-4}-\stackrel{y1}{2}}}{\underset{\textit{\large run}} {\underset{x_2}{3}-\underset{x_1}{(-3)}}} \implies \cfrac{-6}{3 +3} \implies \cfrac{ -6 }{ 6 } \implies - 1[/tex]

[tex]\begin{array}{|c|ll} \cline{1-1} \textit{point-slope form}\\ \cline{1-1} \\ y-y_1=m(x-x_1) \\\\ \cline{1-1} \end{array}\implies y-\stackrel{y_1}{2}=\stackrel{m}{- 1}(x-\stackrel{x_1}{(-3)}) \implies y -2 = - 1 ( x +3) \\\\\\ y-2=-x-3\implies {\Large \begin{array}{llll} y=-x-1 \end{array}}[/tex]

The value of b is 73° as opposite angles of congruent sides are equal in an isosceles triangle.

An angle is created by cοmbining twο rays (half-lines) that have a cοmmοn terminal. The angle's vertex is the latter, while the rays are alternately referred tο as the angle's legs and its arms.

An angle within a shape that has the shape's base as οne οf its sides is knοwn as the base angle οf a shape in geοmetry. Cοnsider the triangle in the image as an example. We can οbserve that the triangle's base side is made up οf an angle B side and an angle C side. As a result, the triangle's base angles are angles B and C.

To know more about complimentary angles visit:-

brainly.com/question/20693383

#SPJ1

Answer:

Approximately 13.89 inches

Step-by-step explanation:

To find the hypotenuse, we use the Pythagorean theorem, in which c is the hypotenuse and a and b are the other two sides of the triangle:

a² + b² = c²

Plug in the values:

c² = 12² + 7²

c² = 144 + 49

c² = 193

c = √193

c ≈ 13.89 inches

The problem asks for the time, we know that the blue whale will reach a depth of 190.65 meters below sea level after 26.7 minutes.

If a function is linear or not, its graph can be examined to determine. A straight line results from the graphing of a linear function. A nonlinear function has some sort of curve in contrast to a linear function.

The slope and y-intercept must first be determined in order to build a linear function. The slope can be determined using the two provided locations (4, -33.7) and (13, -99.4):

slope is the product of (y-change) and (change in x)

slope = (-99.4 - (-33.7)) / (13 - 4)

slope = -65.7 / 9

slope = -7.3

We can now use the point-slope form of a linear equation to obtain the equation of the line since we know its slope:

y - y1 = m(x - x1)

y - (-33.7) = -7.3(x - 4)

y + 33.7 = -7.3x + 29.2

y = -7.3x - 4.5

The following is the linear function that plots the blue whale's depth below sea level against time (x):

y = -7.3x - 4.5

We can plug in this number for y and solve for x to get how long it will take the blue whale to descend 190.65 metres below sea level:

190.65 = -7.3x - 4.5

195.15 = -7.3x \sx = -26.7

We know that the blue whale will descend to a depth of 190.65 metres below sea level in 26.7 minutes because the problem specifically asks for the time.

To know more about Linear Function visit:

https://brainly.com/question/21107621

#SPJ1

Answer:

C) ∠1 ≅ ∠7

Step-by-step explanation:

If ∠1 = ∠3, then ∠3 = ∠7, behind there is written ∠1 = ∠3, so it's A) ∠1 = ∠7.

Answer:

True.

Step-by-step explanation:

Alternate interior angles are congruent, meaning they have equal measure. When we have two parallel lines that are intersected by a transversal, and again my parallel lines are identified by using the same number of arrows, then two special angles are congruent and that is alternate interior angles.