Question

Calcule x:
a) 2x+25=5x-20
b) 5x-20=2x+25

Answer 1

a) 2x - 5x = - 20 - 25
- 3x = -45
x = -45/ - 3 
x = 15

b) 5 x - 2x = 25 + 20
3x = 45
x = 15

Answer 2

2x+25=5x-20
2x-5x=-20-25
-3x=-45 .(-1)
3x=45
X=45/3
X=15

5x-20=2x+25
5x-2x=25+20
3x=45
X=45/3
X=15