Question

b) 10y - 5 (1 + y) = 3 (2y - 2) - 20

Answer 1

10 y - 5 (1 + y) = 3 ( 2y - 2) - 20
10y - 5 - 5y = 6y - 6 - 20
10y - 5y - 6y = - 6 - 20 + 5
- y = - 21    (-1)
y = 21

Answer 2

$10y - 5 (1 + y) = 3 (2y - 2) - 20 \\ \\ 10y - 5 - 5y = 6y - 6 - 20 \\ \\ 5y -5 = 6y - 26 \\ \\ 5y - 6y = -26 + 5 \\ \\ -y = -21 *(-1) \\ \\ => y = 21$