1.3 What is a Function?

Given h(x) = 5 - 9x, find h(8). 

Mathematical Equivalence

ON

For the function f(x) = -3(x-1) find f(0).

• 0
• -3
• 3
• -1

Evaluate f(-5) if f(x) = -2x - 12

• -22
• -2
• -19
• -5

A holiday meal costs $12.50 a person plus a delivery fee of $30.  Which equation represents the amount a holiday meal costs, including delivery, for x people?

• y = 30 + 12.5x 
• y = 12.5 + 30
• y = 12.5 + 30x

Easy Car Rental charges $8.50 an hour plus a rental fee of $25.50. Which equation represents the total charges for x hours?

• y = 8.5 + 25.5
• y = 25.5 + 8.5x
• y = 8.5 + 25.5x

Jerry has $20 and makes $7 per hour. Which equation represents the total amount of money Jerry has after working x hours?

• y = 7x + 20
• y = 7 + 20x
• y = 20 + 7

Sonya has $40 in her lunch account and pays $2 each day to eat lunch.  Which equation can be used to find the amount of money Sonya has left on her account after x days?

• y = 40 + 2x
• y = 40 - 2x
• y = 2 + 40x
• y = 2 - 40x

Sandra has a $20 itunes gift card and spends $3 each month.  Which equation can be used to find how much money Sandra has on her giftcard after x months?

• y = 3x + 20
• y = 3 + 20x
• y = -3x + 20
• y = -20x + 3

Bob has $150 in his savings account and saves $40 per month.

• y = 150 + 40
• y = 40x + 150
• y = 150x + 40

If a question asks you to find f(2), what does that mean?

• Let x = 2

• Let y = 2