求未知数的值.6.2-x =416,7x+2.5x =3.8,(3.8-2)x =14.4,3x -0.5=5.8,4*6+4x _数学解答

求未知数的值.6.2-x =416,7x+2.5x =3.8,(3.8-2)x =14.4,3x -0.5=5.8,4*6+4x =84,10*(15-x )=120

人气：118 ℃　时间：2019-09-18 05:22:15

解答

6.2-x=416
x=-409.8;
7x+2.5x=3.8
9.5x=3.8
x=0.4;
(3.8-2)x =14.4
1.8x=14.4
x=8;
3x-0.5=5.8
3x=6.3
x=2.1
4*6+4x =84
24+4x=84
4x=60
x=15
10*(15-x )=120
150-10x=120
10x=30
x=3