Five less than twice what negative number squared is 157?

Five less than twice what negative number squared is 157 <- put into an expression
-5 + 2(-x^2) = 157
Now simplify:
-5 + -2x^2 = 157
-2x^2 = 162
-2x^2 - 162 = 0
2x^2 + 162 = 0
x^2 + 81 = 0