Question

how do i graph x+y=4 and 2x-y=-7 ?

Answer 1

rewrite it in the form of a line: \(\sf \color{red}{y=mx+b}\)
m = slope = \(\frac{rise}{run}\)
b = y-coordinate (or shifts)

Answer 2

You can do that yourself @alpphaQ
Remember your algebra rules. subtract and isolate \(y\) on just one side.