How do you solve 4(1 - 2j) = 7(2j + 10)?

$4 - 8 j = 14 j + 70$
$4 - 70 - 8 j = 14 j$ ( we substract $70$ on each side )
$- 66 - 8 j = 14 j$
$- 66 = 14 j + 8 j$ ( we add $8 j$ on each side )
$- 66 = 22 j$
$\frac{- 66}{22} = j$ ( we divide by $22$ on each side )
$j = - 3$