alex57school 1.
-6.2x + 2 + 3.6x + 3 = 14.5
-2.6x + 5 = 14.5
-2.6x = 9.5
x = -9.5 / 2.6

2.
-40x - 100 = 100
-40x = 200
x = -5

3.
0.5x + 3 = 0.2x
0.3x = -3
x = -10

4.
6.9 - 9n = 5n - 33.1
40 = 14n
n = 40/14 = 20/7

5.
-21y - 5 + 5.6y - 8 = 20.7
-15.4y - 13 = 20.7
-15.4y = 33.7
y = 33.7 / 15.4