Question

How do you solve for x in the following equation? 3x^2+36x+120=12

Answer 1

3x²+36x+120=12
See that every term is dividable by 3?:
x²+12x+40=4
Subtracting 4 from both sides:
x²+12x+36=0
Now we need to find two numbers that multiplied become 26 and when added become 12:
(x+6)(x+6)=0
Divide both side by (x+6):
x+6=0
x=-6.

Answer 2

Thank you!

Answer 3

You can always check to see if the answer is correct also by plugging in.
x²+12x+40=4
(-6)^2-72+40=4
36-72+40=4
36-22= 4
4 = 4

So -6 is correct.