Question

freaking 2 equations in 2 unknowns with this problem x+y=4
x-y=2

Answer 1

We know:
\[
x+y=4\\
x-y=2
\]So:
\[
x=2+y
\]Substituting for \(x\) in #1:
\[
(2+y)+y=4\implies\\
2+2y=4\implies\\
2y=2\implies\\
y=1
\]Plugging it back into our other equation:
\[
x=2+(1)=3
\]Et voilá.

Answer 2

thank you!