Question

2(х+1)^2 - (х-3)(х+3) = 7+х^2

Answer 1

2(х+1)^2 - (х-3)(х+3) = 7+х^2
2(x^2 + 2x + 1)-(x^2 - 9) = 7 + x^2
2x^2 + 4x + 2 - x^2 + 9 = 7 + x^2
x^2 + 4x + 11 = 7 + x^2
4x + 11 = 7
4x = -4
x = -1