Question

The table shows the height of an elevator above ground level after a certain amount of time. Let y stand for the height of the elevator in feet and let x stand for the time in seconds. Which equation models the data below?
Time (s) Height (ft)
10 235
20 220
40 190
60 160

Answer 1

let's assume the relationship is linear
slope between first pair of points = (220-235)/(20-10) = -15/10 = -1.5

so y = -1.5t + b
using (10,235)
235 = -1.5(10) + b
235 = -15 + b
b = 250

y = -1.5t + 250

testing for last data value
when t=60
y = -1.5(60) + 250 = 160 , yeah!