Verified answer

[tex]a) \: 2x - 10 = 12 \\ 2x = 12 + 10 \\ 2x = 22 \\ x = \frac{22}{2} \\ x = 11 \\ \\ \\ b) \: 3x + 15 = 24 \\ 3x = 24 - 15 \\ 3x = 9 \\ x = \frac{9}{3} \\ x = 3 \\ \\ \\ c) \: 5x - 12 = 13 \\ 5x = 13 + 12 \\ 5x = 25 \\ x = \frac{25}{5} \\ x = 5[/tex]

Espero ter ajudado!