How do you do this and what’s the answer to this i been stuck on this question for litterly 20 mins

Simply 8x squared + 5(7x squared- x) - 2x =

Find the solution of this system of equation -7x+y=-20 9x-3y=36

50 plz, given the system of equations, match the following items. x + 3 y = 5 x - 3 y = -1 a) x-determinant b) y-determinant c) system determinant match the following to the pictures below.