SOLUTION: How do you solve {{{x=1+6sqrt(x-9)}}}?

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Question 314753: How do you solve x=1%2B6sqrt%28x-9%29?
Answer by Edwin McCravy(20055) About Me  (Show Source):
You can put this solution on YOUR website!
x=1%2B6sqrt%28x-9%29

Isolate the radical term on the right

x-1=6sqrt%28x-9%29

Square both sides:

%28x-1%29%5E2=%286sqrt%28x-9%29%29%5E2

%28x-1%29%28x-1%29=36%28x-9%29

x%5E2-x-x%2B1=36x-324

x%5E2-2x%2B1=36x-324

x%5E2-38x%2B325=0

%28x-25%29%28x-13%29=0

x-25=0       x-13=0
   x=25         x=13

Checking x=25

x=1%2B6sqrt%28x-9%29
25=1%2B6sqrt%2825-9%29
25=1%2B6sqrt%2816%29
25=1%2B6%2A4
25=1%2B24
25=25

So x=25 is a solution.

Checking x=13

x=1%2B6sqrt%28x-9%29
13=1%2B6sqrt%2813-9%29
13=1%2B6sqrt%284%29
13=1%2B6%2A2
13=1%2B12
13=13

So x=13 is also a solution.

Edwin