Question

What is the x-coordinate of the point of intersection for these two lines?

Answer 1

You need to use substitution, to do so, you isolate one of the variables x or y in one equation, and then you substitute that equation into the other.

Since you only need to find x, isolate the y in one of the equations

x - 2y = 4

y = $\frac{x}{2} -2$

Plug this in and simplify

9x + 2y = 16

9x + 2($\frac{x}{2} -2$) = 16  Distribute the 2

9x + x - 4 = 16  

10x = 20

x = 2    Your answer is C