解方程 (2x+1)^2+3(x-2)^2-4=7(x+3)(x-3)

2025-03-31 22:38:37
推荐回答(2个)
回答1:

解:4x^2+4x+1+3(x^2-4x+4)-4=7(x^2-9)
7x^2-8x+9=7x^2-63
-8x=-72
x=9

回答2:

先展开得:
4x^2+4x+1+3x-12x+12-4=7x^2-63
-8x+9=-63
8x=72
x=9