Question

You are 9 miles away from home. You start biking home at a speed of 6 miles per hour.

Answer 1

A) y=9-6x, standard form is ax+by=c so add 6x to both sides

6x+y=9

b)  from the first, we had it in slope intercept form, mx+b where b is the y-intercept.  y=-6x+9

So the y-intercept is the point (0,9) which represents the starting distance before you start biking.  You start being 9 miles from your house.

c)  The x intercept occurs when y=0 so:

y=9-6x, so if y=0

0=9-6x

6x=9

x=9/6

x=1.5

This represent the time when you will arrive home and the total time that has elapsed to get there.