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?

Question

Please help I was in regular my whole entire life and now they put me in advance and i have summer HW for algebra which i never did in regular class

Answer 1

Slope is defined as change in y divided by change in x (you'll see this sometimes as Δy/Δx)

 

The slope is ¹/₂, so ¹/₂ = ^Δy/_Δx 

 

The change in y is the change in the y coordinates, which in this case these are -2 and a

The change in x is the change in the x coordinates, which are 4 and -4

 

So the equation becomes 

¹/₂ = ^(-2-a)/_(4-(-4))

 

This simplifies to

 ¹/₂ = ^(-2-a)/₈ 

 

Multiply both sides of the equation by 8 and you get

 

4 = -2-a

 

If you solve for a you'll get

 

a = -6