SOLUTION: solve by completing the square -6x^2+48x-48=0

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Question 175016: solve by completing the square -6x^2+48x-48=0
Answer by Mathtut(3670) About Me  (Show Source):
You can put this solution on YOUR website!
-6x%5E2%2B48x-48=0
:
first factor out -6 out of the x square and x terms
:
-6%28x%5E2-8x%29-48=0
:
now take 1/2 of the x term and square it 8/2=4...4%5E2=16. we also have to add 16(-6) outside the parenthesis to keep an equivalent equation
:
-6%28x%5E2-8x%2B16%29-48%2B96=0
:
now factor completed square
:
-6%28x-8%29%5E2%2B48=0
:
subtract 48 from both sides
:
-6%28x-8%29%5E2=-48
:
divide by -6 on both sides
:
%28x-8%29%5E2=8
:
x-8=sqrt%288%29 and x-8=-sqrt%288%29
:
x=2sqrt%282%29%2B8and x=-2sqrt%282%29%2B8