SOLUTION: Solve. sqrt ( 9x + 67 ) = x + 5

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Question 132556: Solve.
sqrt ( 9x + 67 ) = x + 5
Answer by ptaylor(2198) About Me  (Show Source):
You can put this solution on YOUR website!
sqrt ( 9x + 67 ) = x + 5
sqrt%289x%2B67%29=x%2B5 square both sides--this will get rid of the radical on the left.
9x%2B67=%28x%2B5%29%5E2 get rid of parens
9x%2B67=x%5E2%2B10x%2B25 subtract 9x and also 67 from both sides
9x-9x%2B67-67=x%5E2%2B10x-9x%2B25-67 collect like terms
x%5E2%2Bx-42=0 quadratic in standard form and it can be factored
%28x%2B7%29%28x-6%29=0
x%2B7=0
x=-7------------------------one solution
x-6=0
x=6-------------------------the other solution
CK
substituting x=-7
sqrt+%284%29=-2
+ or - 2=-2--- ok
substituting x=6
sqrt%28121%29=11
+ or -11=11---ok

Hope this helps---ptaylor