求助：初一数学题，我要详细步骤，谢谢；

16(x-y)²-9(x+y)²

2024-11-17 02:48:50

推荐回答（6个）

回答1：

我们也刚学因式分解
16(x-y)²-9(x+y)²
=[4(x-y)+3(x+y)][4(x-y)-3(x+y)]
=(4x-4y+3x+3y)(4x-4y-3x-3y)
=(7x-y)(x-7y)

回答2：

16(x-y)²-9(x+y)²
=[4(x-y)]²-[3(x+y)]²
=[4(x-y)+3(x+y)][4(x-y)-3(x+y)]
=(7x-y)(x-7y)

回答3：

16（x-y)^2 -9(x+y)^2
=16(x^2-2xy + y^2-9（x^2+2xy+y^2）
=16x^2-32xy + 16y^2 - 9x^2-18xy-9y^2
=7x^2-50xy+7y^2

回答4：

16(x-y)²-9(x+y)²
=16(x²-2xy+y²)-9(x²+2xy+y²)
=16x²-32xy+16y²-9x²-18xy-9y²
=(16-9)x²-(32+18)xy+(16-9)y²
=7x²-50xy+7y²

回答5：

16(x-y)²-9(x+y)²
=[4（x-y)]²-[3(x+y)]²
=[4（x-y)+3(x+y)]*[4（x-y)-3(x+y)]
=[4x-4y+3x+3y]*[4x-y4-3x-3y]
=(7x-y)*(x-7y)

回答6：

16(x-y)²-9(x+y)²
=16(x+y)(x-y)-9(x+y)(x+y)
=(x+y)(16x-16y-9x-9y)
=(x+y)(7x-25y)