a) Multiplying all terms by 24 to get rid of denominators:

3x - 312 - 8x = 72
-5x - 312 = 72
-5x = 384
x = -76.8

b) Multiplying all terms by 15 to get rid of denominators:

30 - 105 - 10x = 3x - 12
-10x - 87 = 3x - 12
-13x = 75
x = -5.76923076923077

Therefore, the solutions are x = -76.8 for equation a) and x = -5.76923076923077 for equation b).