Janet took 3h to drive from town a to town b at an average speed of 100km/h. she rested for 30 minutes and traveled to town c at an average speed of 70km/h for the remaining 2h. find janet's average speed for the whole journey.

step-by-step explanation:

let

we know that

the y-intercept is the y-coordinate of the point when the value of x is equal to zero

so

the y-coordinate of the point a is the y-intercept

the answer part a) is

the value of y-intercept is

part b) find the slope m

we know that

the value of the slope is equal to

substitute the values

therefore

the answer part b) is

the value of the slope is equal to

the general answer is

the slope is

the value of y-intercept is