Isabella is travelling in Brazil during the summer, She knows that a 15-minute phone call home to her family costs $45.85 and a 20-minute phone call costs $58.30 sabella only has $55.81 to spend on her phone call. How long can she talk to her family?​

Answer:

Step-by-step explanation:

a=10

Step-by-step explanation:

The question can be interpreted as

F∝a

If we introduce proportionality constant k, we have

F= k.a

28= k. 7

k= 28/7

k= 4

Then the equation can be written as

F= 4.a

To find, a when F = 40?

F= 4.a

40=4 × a

a= 40/4

a= 10

Answer:

F = 40

Step-by-step explanation:

Given F is directly proportional to a then the equation relating them is

F = ka ← k is the constant of proportion

To find k use the condition F = 28 when a = 7 , then

28 = 7k ( divide both sides by 7 )

4 = k

F = 4a ← equation of proportion

When a = 10, then

F = 4 × 10 = 40

Answer:

-12/4

Step-by-step explanation:

Use the slope formula

y2-y1. -8-4

---------- ______ = -12/4

x2-x1. 3-(-1)

Answer:

[tex]\frac{4}{7}[/tex] of a loave of bread per person

Step-by-step explanation:

Step 1:  Convert words to expressions

Seven people in Luisa's Family = 7 people

Four loaves of cinnamon bread = 4 loaves

Step 2:  Divide people from loaves

4 loaves / 7 people  <-  This means they are splitting 4 loaves of bread between 7 people

[tex]\frac{4}{7}[/tex] of a loave of bread per person

Answer:  [tex]\frac{4}{7}[/tex] of a loave of bread per person

Answer:

The answer is A. x= -13

Step-by-step explanation:

The way that you solve it is change the positive 3 to negative and adding the negative 3 to negative 10.

Answer:

x^2 + 5x + 4

Step-by-step explanation:

divide everything by 2

Answer:

2(x+4)(x+1)

Step-by-step explanation:

2x^2+10x+8

1. Take out the greatest common factor. Divide by 2

2(x^2+5x+4)

3. Replace 5x with 1x+4x

2(x^2+1x+4x+4)

4. Spilt the equation in half and factor.

2(x^2+1x) = 2(x(x+1) and 4x+4 = 4(x+1)

5. Combine the new terms

2(x+4)(x+1)

Answer: (21,12)

Step-by-step explanation:

Answer:

x <12/7

Step-by-step explanation:

10x-25-5<-6-4x

10x-30<-6-4x

10x+4x<-6+30

14x<24

answer- x< 12/7

Answer:

x<12/7

Step-by-step explanation:

hope that helps

Answer:

you didnt put the image but it might be 97879

Answer:

288 Inches^3

Step-by-step explanation:

1 Box:-

V=L*W*H, V=6*4*3, V=72 inches^3

4 Box:-

1 Box=72, 72*4=288 inches^3

*I am not 100% sure if this is accurate or not.*

Answer:

The answer is C witch is 288 cubic inches

Step-by-step explanation:

if you muliply all the sides times 4 you would get 288

3x6x4x4=288

Answer:

17

Step-by-step explanation:

Answer:

answers are below

Step-by-step explanation:

a. -6 ≤ 3x < 15

steps in order to solve:

-6 ≤ 3x

= -6/3 ≤ 3x/3

= -2 ≤ x

3x < 15

= 3x/3 < 15/3

= x < 5

=> -2 ≤ x < 5

b. -3 < 2x - 1 < 7

steps in order to solve:

-3 < 2x - 1

= 1 - 3 < 2x - 1 + 1

= -2 < 2x

= -2/2 < 2x / 2

= -1 < x

2x - 1 < 7

= 2x - 1 + 1 < 7 + 1

= 2x < 8

= 2x/2 < 8/2

= x < 4

=> -1 < x < 4

c. 7 < -3n + 1 ≤ 13

steps in order to solve:

7 < -3n + 1

= -1 +7 < -3n + 1 - 1

= 6 < -3n

= 6/-3 < -3n/-3

= -2 > n

-3n + 1 ≤ 13

= -3n + 1 - 1 ≤ 13 -1

= -3n < 12

= -3n/-3 < 12/-3

= n > -4

=> -4 < n < -2

graphs are below.

hope this helps and is right :)

Let's write -9 where we see A:

Let's write 0 where we see B:

(Since B = 0, when it is multiplied by x, it becomes 0 again)

Let's write -2 where we see C:

Now we can move on to solving our equation:)

Let's put the known and the unknown on different sides:

(-2 goes to the opposite side positively)

(it goes as a division because it is in the case of multiplying -9 across)

I could not find the rest of it, but I did not want to delete it for trying very hard. Sorry. It felt like we should take the square root, but I couldn't find it, maybe this can help you a little bit.

Please do not report:(

I hope I got it right, I'm trying to improve my English a little :)

The quadratic equation ax²+ bx + C = 0, whose coefficients are a = -9, b = 0, c = -2 will be -9x² + -2 = 0

An equation is a statement that two expressions, which include variables and/or numbers, are equal. In essence, equations are questions, and efforts to systematically find solutions to these questions have been the driving forces behind the creation of mathematics.

It is given that,coefficients fore the equation,ax²+ bx + C = 0, is a =-9, b = 0, c = -2

We have to write a quadratic equation as,

Any equation of the form ax²+bx+c=0  where x is variable and a, b, and c are any real numbers where a ≠ 0 is called a quadratic equation.

ax² + bx + c = 0

-9x² + 0x + (-2) = 0

-9x² + -2 = 0

-9x² + -2 = 0

Thus, the quadratic equation ax²+ bx + C = 0, whose coefficients are a =-9, b = 0, c = -2 will be -9x² + -2 = 0

Learn more about the equation here,

https://brainly.com/question/10413253

#SPJ6

Answer:

The area is 49.5 cm^2

Step-by-step explanation:

To find the area of the sector, we are going to use the formula for the area of a sector

Mathematically, we have this as;

A = theta/360 * pi * r^2

r = 9 cm and theta = 70

Substituting these values

A = 70/360 * 3.142 * 9^2

A = 49.5 cm^2

Answer:

It is a perfect square expression.

It factors to (x+2)^2

===========================================================

Explanation:

The general format for a perfect square is

(a+b)^2 = a^2 + 2ab + b^2

Which can be seen through the use of the FOIL rule.

Compare x^2+4x+4 with a^2+2ab+b^2, and we have these three equivalences:

Since x^2 = a^2, we can apply the square root to both sides to get a = x. Similarly, 4 = b^2 leads to b = 2. We could get b = -2, but that would mean 2ab = 2x*(-2) = -4x instead of 4x. So we'll stick with b = 2 instead.

Because a = x and b = 2, we then can say:

(a+b)^2 = a^2 + 2ab + b^2

(x+2)^2 = x^2 + 2*x*2 + 2^2

(x+2)^2 = x^2 + 4x + 4

Showing that x^2+4x+4 factors to (x+2)^2.

Answer:

7 seconds

Step-by-step explanation:

Hello There!

I had created a graph to make it easier to understand

So when y = 0 is when the ball is at the ground

when y = 0 x = 7 so it took about 7 seconds for the ball to hit the ground

Answer:

7

Step-by-step explanation:

Answer:

12

Step-by-step explanation:

2*12-4=20

Answer:

x = 12

Step-by-step explanation:

2x - 4 = 20

2x = 20 + 4

2x = 24

x = 24/2

x = 12

Answer:

figure b

Step-by-step explanation:

cuz yez

Answer:

$141

Step-by-step explanation:

1200-(1200*30/100 )

and i did that six time each tume with the new numbers i got

Answer: 0.13

3 times 0.044 =0.13

Step-by-step explanation:

Answer:

Step-by-step explanation:

This is because 4 ft x 8 ft = 24 feet

24 feet times 12 (this is because there 12 inches in a foot)

288 inches

Answer:

1) Growth

2) y = 3

Explanation:

1) y = a*b^x

   y = 3 + 2^x

2 > 1, so it's growth

Answer:

8 plates per stack

Step-by-step explanation:

Answer:

8 plates per stack

Step-by-step explanation:

if wrong I am so sorry