a)
[tex]3x + 7 = 31 \\ 3x = 24 \\ x = 8[/tex]
b)
[tex] - 2x + 10 = 6 \\ - 2x = - 4 \\ x = 2[/tex]
c)
[tex]3x - 10 = 14.5 + 2x \\ x = 24.5[/tex]
d)
[tex]9(x - 8) = 36 \\ 9x - 72 = 36 \\ 9x = 108 | \div 9 \\ x = 12[/tex]
e)
[tex] \frac{2x - 2}{3} - \frac{x + 1}{2} = \frac{1}{6} | \times 6 \\ 4x - 4 - 3x - 3 = 1 \\ x = 8[/tex]
