Respuestas
1)
6x - 20 = 3x + 10
6x - 3x = 10 + 20
3x = 30
x = 30/3
x = 10
2)
8x + 3 = 5x + 15
8x - 5x = 15 - 3
3x = 12
x = 12/3
x = 4
3)
7x - 6 = 4x + 3
7x - 4x = 3 + 6
3x = 9
x = 9/3
x = 3
4)
10x - 15 = 5x + 10
10 - 5x = 10 + 15
5x = 25
x = 25/5
x = 5
5)
8x + 2 = 4x + 6
8x - 4x = 6 - 2
4x = 4
x = 4/4
x = 1
6)
7x - 9 = 5x + 5
7x - 5x = 5 + 9
2x = 14
x = 14/2
x = 7
7)
6x - 2 = 2x + 6
6x - 2x = 6 + 2
4x = 8
x = 8/4
x = 2
8)
9x + 6 = 5x + 30
9x - 5x = 30 - 6
4x = 24
x = 24/4
x = 6
9)
5x - 7 = 3x + 1
5x - 3x = 1 + 7
2x = 8
x = 8/2
x = 4
10)
8x - 9 = 4x + 3
8x - 4x = 3 + 9
4x = 12
x = 12/4
x = 3
11)
10x - 20 = 5x + 20
10x - 5x = 20 + 20
5x = 40
x = 40/5
x = 8
12)
9x + 7 = 5x + 15
9x - 5x = 15 - 7
4x = 8
x = 8/4
x = 2
Espero haberte ayudado. Suerte en los estudios ≧◠◡◠≦.