Question

The temperature, t, in Burrtown starts at 21°F at midnight, when h = 0. For the next few hours, the temperature drops 4 degrees every hour.

Which equation represents the temperature, t, at hour h?

A. t = 4h + 21
B. t = –21h + 4
C. t = –4h + 21
D. t = 21h + 4

Answer 1

C.
The starting temperature is 21 degrees, so this is the y-intercept.

Since the temperature dropping, the slope of 4 is negative.

The result in slope-intercept form is -4h+21

Answer 2

C.
The starting temperature is 21 degrees, so this is the y-intercept.