Answer
(a) $m = \frac{9}{5}$
The slope shows that the change in Fahrenheit temperature is $\frac{9}{5}$ degrees for each degree change in Celsius temperature.
(b) $F = \frac{9}{5}C+32$
Work Step by Step
To find the slope if the line $m$, we can use the point (0,32) and the point (20,68).
$m = \frac{\Delta F}{\Delta C}$
$m = \frac{68-32}{20-0}$
$m = \frac{36}{20}$
$m = \frac{9}{5}$
The slope shows that the change in Fahrenheit temperature is $\frac{9}{5}$ degrees for each degree change in Celsius temperature.
(b) When C = 0 then F = 32, so the y-intercept is 32.
Note that F is on the y-axis and C is on the x-axis.
$y = mx + b$
$F = \frac{9}{5}C+32$
