Question

(x + 2)2 + 8(x - 1)(x + 1) =9x² + 116
хэлп​

Answer 1

$(x + 2)^2 + 8(x - 1)(x + 1) =9x^2 + 116\\x^2+4x+4+8x^2-8=9x^2+116\\4x=120\\x=30$