4. For the three-step question that follows, provide your answer to each question in the given workspace. Identify each step with a coordinating response. Be sure to clearly label each part of yo response as Part A, Part B, and Part C.

Part A: Ava was asked to find the value of the expression 13t - 8r2 when t = -10 and r =

2. Her work is shown below, but she made a mistake. What was Ava's mistake?

13t - 8r2

13( - 10) - 80 - 2)

131 – 10) - 804)

130 - 8(4)

-138 - (4)

-552

Part B: Evaluate the expression correctly.

Part C: Show all of your work to support your answer to Part B.

Step-by-step explanation:

Given the expression f(t, r) = 13t - 8r²

We are to justify Ava solution at when t = -10 and r = -2

Substitute the given values into the function given;

f(t, r) = 13t - 8r²

f(-10, -2) = 13(-10) - 8(-2)²

f(-10, -2) = 13(-10) - 8(4)

f(-10, -2) = -130-8(4)

f(-10, -2) = -130 - 32

f(-10, -2) = -152

Ava made a mistake in step 4. She added -130 to -8 to get -138 before multiplying by 4 thereby falsifying her result. She must have multiplied -4 by 8 before adding the resulting answer to -130 as shown. Hence the correct answer is -152

45

step-by-step explanation:

fabric (square meters)                   cloaks

7                                                           21

4/3                                                         4

step-by-step explanation:

we are told that harry needs 2 square meters of fabric for every 6 wizard cloaks he makes.

1. first of all we will find how many cloaks can be made from 1 square meter of fabric by dividing 6 by 2.

we can see that 3 cloaks can be made from 1 square meter of fabric. now we will multiply 3 by 7 to find number of cloaks made from 7 square meters of fabric.

therefore, harry will make 21 cloaks from 7 square meters of fabric.

2. let us find how many square meters of fabric will be needed to make 4 cloaks.

first of all we will find fabric needed for 1 cloak by dividing 2 by 6.

we can see that fabric needed for 1 cloak is   square meter. now we will multiply   by 4 to find fabric needed for 4 cloaks.