用分解因式法解下列方程①(4X-1)(5X+7)=0②3X(X-1)=2-2X③(2X+3)²=4(2X+3)④2(X-3)²=X²-9
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![用分解因式法解下列方程①(4X-1)(5X+7)=0②3X(X-1)=2-2X③(2X+3)²=4(2X+3)④2(X-3)²=X²-9](/uploads/image/z/5300106-42-6.jpg?t=%E7%94%A8%E5%88%86%E8%A7%A3%E5%9B%A0%E5%BC%8F%E6%B3%95%E8%A7%A3%E4%B8%8B%E5%88%97%E6%96%B9%E7%A8%8B%E2%91%A0%EF%BC%884X-1%EF%BC%89%EF%BC%885X%2B7%EF%BC%89%3D0%E2%91%A13X%EF%BC%88X-1%EF%BC%89%3D2-2X%E2%91%A2%EF%BC%882X%2B3%EF%BC%89%26%23178%3B%3D4%EF%BC%882X%2B3%EF%BC%89%E2%91%A32%EF%BC%88X-3%EF%BC%89%26%23178%3B%3DX%26%23178%3B-9)
用分解因式法解下列方程①(4X-1)(5X+7)=0②3X(X-1)=2-2X③(2X+3)²=4(2X+3)④2(X-3)²=X²-9
用分解因式法解下列方程
①(4X-1)(5X+7)=0
②3X(X-1)=2-2X
③(2X+3)²=4(2X+3)
④2(X-3)²=X²-9
用分解因式法解下列方程①(4X-1)(5X+7)=0②3X(X-1)=2-2X③(2X+3)²=4(2X+3)④2(X-3)²=X²-9
①(4X-1)(5X+7)=0
x1=1/4, x2=-7/5
②3X(X-1)=2-2X
3X(X-1)=-2(X-1)
3X(X-1)+2(X-1)=0
(3X+2)(X-1)=0
x1=-2/3, x2=1
③(2X+3)²=4(2X+3)
(2X+3)²-4(2X+3)=0
(2X+3)(2X+3-4)=0
∴X1=-2/3, X2=1/2
④2(X-3)²=X²-9
2(X-3)²-(X+3)(X-3)=0
(X-3)[2(x-3)-(X+3)]=0
(x-3)(x-9)=0
∴X1=3,X2=9
①(4X-1)(5X+7)=0
x=1/4或x=-7/5
②3X(X-1)=2-2X
=3X²-3x+2x-2
=(x-2)(3x+1)
x=2或x=-1/3
③(2X+3)²=4(2X+3)
当2x+3=0时,本式成立,x=-3/2
当2x+3不等于0时,得2x+3=4,x=1/2
④2(X-3)...
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①(4X-1)(5X+7)=0
x=1/4或x=-7/5
②3X(X-1)=2-2X
=3X²-3x+2x-2
=(x-2)(3x+1)
x=2或x=-1/3
③(2X+3)²=4(2X+3)
当2x+3=0时,本式成立,x=-3/2
当2x+3不等于0时,得2x+3=4,x=1/2
④2(X-3)²=X²-9
2(X-3)²=(X-3)(x+3)
当x-3=0时,本式成立,x=3
当x-3不等于0时,得2(x-3)=x+3,得x=9
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①(4X-1)(5X+7)=0→4x-1=0或5x+7=0→x1/4或x=-7/5
②3X(X-1)=2-2X→3x(x-1)-(2-2x)=0→3x(x-1)+(2x-2)=0
→3xx-1)+2(x-1)=0→(x-1)(3x+2)=0→x-1=0或3x+2=0→x=...
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①(4X-1)(5X+7)=0→4x-1=0或5x+7=0→x1/4或x=-7/5
②3X(X-1)=2-2X→3x(x-1)-(2-2x)=0→3x(x-1)+(2x-2)=0
→3xx-1)+2(x-1)=0→(x-1)(3x+2)=0→x-1=0或3x+2=0→x=1或x=-2/3
③(2X+3)²=4(2X+3)→(2x+3)²-4(2x+3)=0→(2x+3)(2x+3-4)=0
→2x+3=0或2x-1=0→x=-3/2或x=1/2
④2(X-3)²=X²-9→2(x-3)²=(x+3)(x-3)→2(x-3)²-(x+3)(x-3)=0
→(x-3))[2(x-3)-(x+3)]=0→(x-3)(x-9)=0
→x-3=0或x-9=0→x=3或x=9
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