Nx 7 = 49 what is the missing added?

Last one and the bottom answer choice is y=(x-4)^2+1 you guys!

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.

Hurry which expression is equivalent to 3√x^5y?