9x^2 -7(4+x)(4-x) -(1-4x)2 = 159x^2 -7(16-x^2) -2 +8x -15 = 09x^2 -112 +7x^2+8x -17 = 016x^2 +8x -127 = 0D = 64 +4*16*127 = 8192x = (-8 -√8192) / 32 = -8/32 -√(8192/32²) = -1/4 -√8 = -0,25 -2√2x = (-8 +√8192) / 32 = -8/32 +√(8192/32²) = -1/4 +√8 = -0,25 +2√2____________________________Или если там всё-таки квадрат, а не умножение на два:9x^2 -7(4+x)(4-x) -(1-4x)^2 = 159x^2 -7(16-x^2) -(1 -8x +16x^2) -15 = 09x^2 -112 +7x^2 -1 +8x -16x^2 -15 = 016x^2 -16x^2 +8x -128 = 08x -128 = 08x = 128x = 16Ответ: 16