八年级上册数学整式乘法①a(a-b)-(a+b)(-2b)

题目

八年级上册数学整式乘法①a(a-b)-(a+b)(-2b)
②化简求值(3x+2y)(4x-5y)-11(x+y)(x-y)+5xy,其中x=三又二分之一,y=负二又二分之一
3化简求值[xy(1-x)-2x(y-½)]*2x^2+2x^3y^2(X+1),其中x=-1,y=3
4解方程(X-3）(x-2)=(X+9）(x+1）+4
5 已知x²-8x-3=0,求(X-1）(X-3）(x-5)（x-7)的值

答案

2.(3x+2y)(4x-5y)-11(x+y)(x-y)+5xy =12x²-15xy+8xy-10y²-11（x²-y²）+5xy =12x²-15xy+8xy-10y²-11x²+11y²+5xy =x²-2xy+y² =（x-y...