If you are solving for x then here’s how:
(3x2 + 4x - 12) = (x + 5)
Remove the x on the left by remove one x from both of the sides.
(3x2 + 3x - 12) = 5
Add 12 onto both sides
(3x2 + 3x) = 17
Multiply
(6 + 3x) = 17
Take away 6 from both sides
3x = 11
Divide by 3 on both sides
x = 3.666 recurring
