Which and what is the greatest rate of vertical change

Question

I have 3 linear function in slope intercept form

Y=-10x+15000, y=4x-98, and Y=-12x+100 and I was asked out of the 3 which had the greatest rate of vertical change. I would like to know which has the greatest rate of vertical change and what exactly greatest rate of vertical change means.

Answer 1

slope = the coefficient of the x term, when the equation is solved for y

slope = "rise over run" the change in y divided by the change in x

if you want the greatest increase vertically, y=4x-98 is the only line that goes up, as you go left to right

if you want the greatest vertical change,(positive or negative), then y=-12+100 has the largest change in y for a given change in x