Question

Решите уравнение 9х^2-7(x+4)*(4-x)-(1-4x)^2=15

Answer 1

9х^2-7(x+4)*(4-x)-(1-4x)^2=15

9х^2+7x^2-112-1+8x-16x^2=15

8x=128

x=16

Answer 2

9x²-7(x+4).(4-x)-(1-4x)²=15
9x²-7(16-x²)-1+8x-16x²=15
9x²-112+7x²-1+8x-16x²=15
8x-113=15
8x=128
x=16