几个初三数学题,快~急用,答得快又好加分~用分解因式法解下列方程1.2(x-3)^2=x^2-92.(x-2)^2=(2x+3)^23.(x-2)(x-3)=124.2x+6=(x+3)^25.2y^2+4y=y+2

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几个初三数学题,快~急用,答得快又好加分~用分解因式法解下列方程1.2(x-3)^2=x^2-92.(x-2)^2=(2x+3)^23.(x-2)(x-3)=124.2x+6=(x+3)^25.2y^2+4y=y+2
几个初三数学题,快~急用,答得快又好加分~
用分解因式法解下列方程
1.2(x-3)^2=x^2-9
2.(x-2)^2=(2x+3)^2
3.(x-2)(x-3)=12
4.2x+6=(x+3)^2
5.2y^2+4y=y+2

几个初三数学题,快~急用,答得快又好加分~用分解因式法解下列方程1.2(x-3)^2=x^2-92.(x-2)^2=(2x+3)^23.(x-2)(x-3)=124.2x+6=(x+3)^25.2y^2+4y=y+2
1.2(x-3)^2=x^2-9
2(x-3)^2-(x+3)(x-3)=0
(x-3)(2x-6-x-3)=0
(x-3)(x-9)=0
x=3,x=9
2.(x-2)^2=(2x+3)^2
(x-2)^2-(2x+3)^2=0
[(x-2)+(2x+3)][(x-2)-(2x+3)]=0
(3x+1)(-x-5)=0
x=-1/3,x=-5
3.(x-2)(x-3)=12
x^2-5x+6-12=0
x^2-5x-6=0
(x-6)(x+1)=0
x=6,x=-1
4.2x+6=(x+3)^2
(x+3)^2-2(x+3)=0
(x+3)(x+3-2)=0
(x+3)(x+1)=0
x=-3,x=-1
5.2y^2+4y=y+2
2y^2+3y-2=0
(2y-1)(y+2)=0
y=1/2,y=-2