Question

解方程2X-1.8=X+2.4 3X-2(10-X)=15 (2X+3)*2=5X-4 18/4X-3=9 (4-X)*7=(X-4)*9 6.2*(3X-4)+7*(4-X)=4X

Answer 1

2X-1.8=X+2.4
解：2X-X=2.4+1.8
X=4.2

3X-2(10-X)=15
解：3X-20+2X=15
3X+2X=15+20
5X=35
X=7

(2X+3)*2=5X-4
解： 4X+6=5X-4
5X-4X=6+4
X=10

18/4X-3=9
解：2分之9X=9+3
X=12除以2分之9
X=2又3分之2

(4-X)*7=(X-4)*9
解：28-7X=9X-36
9X+7X=28+36
16X=64
X=4
2*(3X-4)+7*(4-X)=4X
解：6X-8+28-7X=4X
7X+4X-6X=28-8
5X=20
X=4

Answer 2

2X-1.8=X+2.4
2X-X=2.4+1.8
X=4.2
3X-2(10-X)=15
3X-20+2X=15
3X+2X=15+20
5X=35
X=7
(2X+3)*2=5X-4
4X+6=5X-4
4X-5X=-4-6
-X=-10
X=10
18/4X-3=9
18-12X=36X
36X+12X=18
48X=18
X=8/3
(4-X)*7=(X-4)*9
28-7X=9X-36
9X+7X=28+36
16X=64
X=4
2*(3X-4)+7*(4-X)=4X
6X-8+28-7X=4X
6X-7X-4X=8-28
-5X=-20
X=4