用配方法解下列方程①:x²+10x+16=0 ②:x²-x-¾=0

2025-03-05 12:06:09
推荐回答(2个)
回答1:

x²+10x+16=0
x^2+10x+25=9
(x+5)^2=9
所以 x+5=3 x=2
或 x+5=-3 x=-8

x²-x-¾=0
x^2-x+1/4=1
(x-1/2)^2=1

所以x-1/2=1 x=3/2
或x-1/2=-1 x=-1/2

回答2:

①:x²+10x+16=0
(x+2)(x+8)=0
x1=-2 x2=-8
②:x²-x-¾=0
(x-3/2)(x+1/2)=0
x1=3/2 x2=-1/2 .