4(2x-1)²=9(3-x)²
4(2x-1)²-9(3-x)²=0
[2(2x-1)-3(3-x)][2(2x-1)+3(3-x)]=0
(4x-2-9+3x)(4x-2+9-3x)=0
(7x-11)(x+7)=0
7x-11=0 x+7=0
∴
x₁=11/7
x₂=-7
(y-1)(y+3)=12
y²+2y-3-12=0
y²+2y-15y=0
(y+3)(y-5)=0
y+3=0 y-5=0
∴
y₁=-3
y₂=5
4(2x-1)²-9(3-x)²=0
[2(2x-1)-3(3-x)][2(2x-1)+3(3-x)]=0
(4x-2-9+3x)(4x-2+9-3x)=0
(7x-11)(x+7)=0
7x-11=0 x+7=0
∴
x₁=11/7
x₂=-7
(y-1)(y+3)=12
y²+2y-3-12=0
y²+2y-15y=0
(y+3)(y-5)=0
y+3=0 y-5=0
∴
y₁=-3
y₂=5
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第1个回答 2015-09-27
解（4）y²+2y-3-12=0
y²+2y-15=0
(y-3)(y+5)=0
∴y=3 y=-5追答
y²+2y-15=0
(y-3)(y+5)=0
∴y=3 y=-5追答
解:4(2x-1)²-9(3-x)²=0
(4x-2)²-(9-3x)²=0
(4x-2-9+3x)(4x-2+9-3x)=0
(7x-11)(x+7)=0
x=11/7,x=-7
第2个回答 2015-09-27
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