解7+20%x=50%x这个方程还有还有,x:7.5=2分之15x—5分之6=5分之3x

问题描述:

解7+20%x=50%x这个方程
还有还有,x:7.5=2分之1
5x—5分之6=5分之3x

(1)
7 + 20%x = 50%x
7 + 0.2x = 0.5x
0.3x = 7
3x = 70
x = 70 / 3
(2)
x :7.5 = 1/2
x = 3.75
(3)
5x - 6/5 = 3x/5
两边同乘以 5 ,得
25x - 6 = 3x
22x = 6
x = 3/11