Question

A line passes through the point (4, -2) and has a slope of

1/2


What is the value of a if the point (-4, a) is also on the line?

-6
-5
5
6
HELP!!!!!!

Answer 1

a would equal -6

Explanation:

First, use y=mx+b to find the y-intercept (plug in (x,y) and 1/2 for m)

-2=4(1/2)+b this would simplify to -2=2+b

Subtract 2 from both sides

-2-2=2-2+b

b=-4 our y-intercept is -4

our new equation would be y=1/2x-4, graph this equation and find a point that correlates with the -4 on the y-axis and is in the line, that point will be -6

To prove our point we can write the equation using our new points (-4,-6) and we will get -4 as our "b" or y-intercept

-6=-4(1/2)+b

-6=-2+b add -2 to both sides

-4=b