①(x-5)(x+7)=4 ②4x²-4x-3=0①(x-5)(x+7)=4 ②4x²-4x-3=0

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①(x-5)(x+7)=4 ②4x²-4x-3=0①(x-5)(x+7)=4 ②4x²-4x-3=0

①(x-5)(x+7)=4 ②4x²-4x-3=0①(x-5)(x+7)=4 ②4x²-4x-3=0
①(x-5)(x+7)=4 ②4x²-4x-3=0
①(x-5)(x+7)=4 ②4x²-4x-3=0

①(x-5)(x+7)=4 ②4x²-4x-3=0①(x-5)(x+7)=4 ②4x²-4x-3=0
1、
x²+2x-35=4
x²+2x+1=4+35+1
(x+1)²=40
x+1=±2√10
x=-1-2√10,x=-1+2√10
2、
4x²-4x-3=0
(2x-3)(2x+1)=0
x=3/2,x=-1/2

①(x-5)(x+7)=4
x²+2x-35=4
x²+2x+1= 40
(x+1)²=40
x+1=±2√10
x1=-1+2√10, x2=-1-2√10
②4x²-4x-3=0
4x²-4x+1=4
(2x-1)²=4
2x-1=±2
x1=3/2, x2=-1/2

x²+2x-35=4
x²+2x-39=0
x= -1 ± 2√10
4x²-4x-3=0
4x²-4x+1=4
(2x-1)²=2²
2x-1=2,或者2x-1=-2
x=1.5,或者:x = -0.5