How do you solve 6x^2 + 36x + 18 = 06x2+36x+18=0 using completing the square?

1 Answer
MeneerNask
Jun 11, 2015

First thing to notice, is that everything can be divided by 6

Explanation:

So the equation becomes:
x^2+6x+3=0x2+6x+3=0

Completing the square is you take half of the number with xx and square it, which would be x^2+6x+9x2+6x+9, but to even out with the 33 you've got, you write 3=9-63=9−6:
x^2+6x+9-6=0->x2+6x+9−6=0→
(x+3)^2-6=0->(x+3)^2=6->(x+3)2−6=0→(x+3)2=6→
x+3=+-sqrt6->x=-3+-sqrt6x+3=±√6→x=−3±√6

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