24-0.5X= 12.8
0.5X=24- 12.8
X=22.4
(24.5-X)×2- 13=20
49-2X- 13=20
2X=36-20
X=8
5X-X+ 1.8=3.6
4X=3.6- 1.8
X= 1.8÷4
X=0.45
(X+2. 1)÷3= 10.5
(X+2. 1)÷3×3= 10.5×3
X+2. 1=3 1.5
X=3 1.5-2. 1
X=29.4
3.5×X= 105
X= 105÷3.5
X=30
13.06-X=8.07
X= 13.06-8.07
X=4.99
0.2(X-3.5)= 1
0.2X-0.7= 1
0.2X= 1+0.7
X=8.5
12X-3.5X+85
This problem is not an equation.
1.2X-X=35
0.2X=35
X=35÷0.2
X= 175
3-3 times =0.3
3X=3-0.3
3X=2.7
x = 2.7 \3
X=0.9
3.5×6-0.2X= 1 1.4
2 1-0.2X= 1 1.4
0.2X=2 1- 1 1.4
0.2X=9.6
X=48
3.5×(6-0.2X)= 17.5
2 1-0.2X= 17.5
0.2X=2 1- 17.5
0.2X=3.5
X=3.5÷0.2
X= 17.5