Question

how to solve system attached

Answer 1

I would solve this system by substitution. Are you familiar with that method?

Answer 2

Hint:
I solve the second equation for y, and I get:
y=x+5
then I substitute that solution into the first equation, so I can write:
\[\Large x + 5 = {x^2} + 2x - 7\]

Answer 3

Yep, that works. And finish solving for x using quadratic solving methods.