9- x/5 = 3
Simplify both sides
9- x/5 = 3
9+ -1/5 x = 3
-1/5 x +9 = 3
Subtract 9 from both sides
-1/5 x +9-9 = 3-9
-1/5 x = -6
Multiply both sides by 5/(-1)
(5/-1 )*(-1/5 x )= (5/-1 ) * (-6)
x = 30
I hope that's help and if you have question please just let me know !