trig
posted by Anonymous on .
how do i solve this completing the square problem: 3x^2+12x+10=0

3x^2+12x+10=0
3(x^2+4x+10/3)=0
(x+2)²4+10/3=0
(x+2)²(√(2/3))²=0
(x+2+√(2/3))(x+2√(2/3))=0
therefore
x=2√(2/3) or 2+√(2/3) 
divide by 3
x^2+4x+10/3=0
x^2+4x + ???= 10/3 + ???
well, look at the second term. take one half of it, and square it, add to both sides.
x^2+4x+4=10/3+4= 10/3+12/3
(x+2)^2= 2/3
take the square root of each side.
x+2= +sqrt 2/3
x=2+sqrt 2/3
check that.