Question

After noon, the number of people at wal-mart grows steadily until 6:00 P.M. If the equation y=228+58x represents the number of people in the store x hours afternoon:
a. how many peple were in the store at noon?
b. at what rate is the number of shoppers growing?
c. When were there 402 shoppers in the store?

Answer 1

a.) 228 (because x=0)
b.)rate is 58 ppl per hour (slope)
c.)y=402...so x=3

Answer 2

if x represents hours after noon, then at noon, x is zero hours after noon because no time has passed yet. So, for part A, you need to set x=0 and then solve.
For part b, they are essentially asking for the slope. (the rate of change of the line). If y is representing people and x is time, then as x increases by each hour, 58 more people are showing up to shop.
For part C, they want to know at what time will there be a total of 402 people shopping, so you plug that in for y and then solve.