Carolina receives an allowance that is tied to completing her chores during the week. She starts off with an allowance of $20. She has five chores to complete during the week, and for each chore she completes, she receives $3. However, for each chore that is not done by the end of the week, she loses $4 from her allowance. a. Write an expression describing Carolina's allowance as a function of the number of chores, C, that she completes during the week.

b. If Carolina completes 4 chores, what is her allowance?

a. x = 7c

b. $28

Step-by-step explanation:

Her allowance starts at $20.

Out of 5 chores, for each chore she completes, she receives $3.

For each chore that she does not complete, she loses $4.

a. An expression describing her allowance

Let her total allowance be x:

x = 20 + (3 * c) + (-4 * (5 - c))

x = 20 + 3c - 20 + 4c

x = 20 - 20 + 7c

x = 7c

b. If she completes 4 chores, she will receive:

x = 7 * 4 = $28

step-by-step explanation:

first, eliminate the parenthesis:

3

x

+

2

−

4

x

second, group like terms:

3

x

−

4

x

+

2

third, combine like terms:

(

3

−

4

)

x

+

2

→

−

1

x

+

2

→

−

x

+

2