SOLUTION: Solve q=sqrt(q) + 6

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Question 110041: Solve q=sqrt(q) + 6
Found 2 solutions by HyperBrain, edjones:
Answer by HyperBrain(694) About Me  (Show Source):
You can put this solution on YOUR website!
q=sqrt%28q%29%2B6
sqrt%28q%29%2B6=q
sqrt%28q%29%2B6-6=q-6
sqrt%28q%29%2B0=q-6
sqrt%28q%29=q-6
%28sqrt%28q%29%29%5E2=%28q-6%29%5E2
sqrt%28q%5E2%29=q%5E2-12q%2B36
q=q%5E2-12q%2B36
q%5E2-12q%2B36=q
q%5E2-12q-q%2B36=q-q
q%5E2-13q%2B36=0

quadratic formula:
q=%2813%2B-sqrt%2813%5E2-4%2A1%2A36%29%29%2F%282%2A1%29
q=%2813%2B-sqrt%28169-144%29%29%2F%282%29
q=%2813%2B-sqrt%2825%29%29%2F%282%29
q=%2813%2B-+5%29%2F%282%29
q=%2813%2B5%29%2F%282%29 or q=%2813-5%29%2F%282%29
q=18%2F2=9 or q=8%2F2=4

Power up,
HyperBrain!

Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
q=sqrt(q)+6
q-6=sqrt(q)
q^2-12q+36=q square both sides.
q^2-13q+36=0
(q-9)(q-4)=0
q=9, q=4
Always check these.
9=sqrt(9)+6 true
4=sqrt(4)+6 false
q=9 is the only answer.
Ed