(400-5x)(8-4x)=4800解方程怎么解?化简的话是都除以2还是4?_数学解答

(400-5x)(8-4x)=4800解方程怎么解?
化简的话是都除以2还是4?

人气：453 ℃　时间：2020-06-27 05:00:49

解答

(400-5x)(8-4x)=4800
5(80-x)*4(2-x)=4800
(80-x)(2-x)=240
160-82x+x^2=240
x^2-82x-80=0
(x-41)^2=1761
x-41=（+/-)根号1761
X1=41+根号1761
X2=41-根号1761