(40-40x)x+40x=40-32.4
问题描述:
(40-40x)x+40x=40-32.4
答
40x-40x2+40x=7.8
40x2-80x+7.8=0
(40-40x)x+40x=40-32.4
40x-40x2+40x=7.8
40x2-80x+7.8=0