1. Write the equation, in slope-intercept form, of the line with slope 9 and y intercept (0, --13).

Step-by-step explanation:

Slope-intercept form is , where m is the slope, and b is the y-intercept. They tell us the slope is 9, so . They also tell us that the y-intercept is (0,-13), which means that . Plugging both of those values in gives us the equation:

4a. is 3 miles every hour

4b. is 1/3 of an hour per mile

step-by-step explanation:

y=3x+4

step-by-step explanation:

given the points a(0,4) and b(-4, -8)

eqn of line ab: (y-4)/(x-0)=(-8-4)/(-4-0)

(y-4)/x=-12/-4=3

y=3x+4