用适当方法解下列方程:(1)(x-3)(x+7)=-9 (2)x²-3x-10=0(3)(2y+1)²-8(2y+1)+15=0(4)(x-√3)=√2x(x-√3) (5)√3(3x-2)=(2-3x)(x+1)

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用适当方法解下列方程:(1)(x-3)(x+7)=-9 (2)x²-3x-10=0(3)(2y+1)²-8(2y+1)+15=0(4)(x-√3)=√2x(x-√3) (5)√3(3x-2)=(2-3x)(x+1)
用适当方法解下列方程:(1)(x-3)(x+7)=-9 (2)x²-3x-10=0
(3)(2y+1)²-8(2y+1)+15=0(4)(x-√3)=√2x(x-√3) (5)√3(3x-2)=(2-3x)(x+1)

用适当方法解下列方程:(1)(x-3)(x+7)=-9 (2)x²-3x-10=0(3)(2y+1)²-8(2y+1)+15=0(4)(x-√3)=√2x(x-√3) (5)√3(3x-2)=(2-3x)(x+1)
(1)(x-3)(x+7)=-9
x^2+4x-21+9=0
(x-2)(x+6)=0
x=2或x=-6
(2)x²-3x-10=0
(x-5)(x+2)=0
x=5或x=-2
(3)(2y+1)²-8(2y+1)+15=0
(2y+1-3)(2y+1-5)=0
y=1或y=2
(4)(x-√3)=√2x(x-√3)
(x-√3)-√2x(x-√3)=0
(x-√3)(1-√2x)=0
x=√3或x=√2/2
(5)√3(3x-2)=(2-3x)(x+1)
√3(3x-2)-(2-3x)(x+1)=0
√3(3x-2)+(3x-2)(x+1)=0
(3x-2)(√3+x+1)=0
x=2/3或x=-√3-1