Question

You have a $50 coupon from the manufacturer good for the purchase of a cell phone. The store where you are purchasing your cell phone is offering a 20% discount on all cell phones. Let x represent the regular price of the cell phone. Use the word bank below to complete each blank. [Click on the phrase to fill in the blank. You do NOT need to type.] A.] Suppose only the 20% discount applies. Find a function \large f\left(x\right) that models the purchase price of the cell phone. f(x)

Answer 1

`f(x) = 0.80x`

Explanation:

Given

`x \to price`

`discount \to 20\%`

`coupon = \$50`

Required

The function f(x) if only the discount applies

20% discount implies that the price will be reduced by 20%.

So, the function is:

`f(x) = Price - Price * Discount`

`f(x) = x - x * 20\%`

Factorize

`f(x) = x(1 - 20\%)`

Express percentage as decimal

`f(x) = x(1 - 0.20)`

`f(x) = x(0.80)`

`f(x) = 0.80x`