membership warehouse clubs offer shoppers low prices

Question

Membership warehouse clubs offer shoppers low​ prices, along with rewards of cash back on club purchases. If the yearly fee for a warehouse club membership is​ $100 and the reward rate is

4​%

on club purchases for the​ year, then the linear equation

y=100−0.04x

models the actual yearly cost of the membership​ y, in dollars. Here x represents the yearly amount of club​ purchases, also in dollars.

​a) Determine the actual yearly cost of the membership if club purchases for the year

are

​$1500.

Answer 1

Hi Mira!

For this question, you're given a linear equation y=100-0.04x, where 100 is the fee for the membership and -0.04x is the savings you have because of the membership (x is the amount spent while the coefficient is the 4% saved).

If $1500 is spent, then you plug in that value for x to solve.

y=100-0.04(1500)

y=100-60

y=40

In this case, the total cost of the membership is $40