SOLUTION: u-3(square root of u)-10=0 Hint: let x= square root of u, so x squared = u

Algebra ->  Square-cubic-other-roots -> SOLUTION: u-3(square root of u)-10=0 Hint: let x= square root of u, so x squared = u      Log On


   

Question 241792: u-3(square root of u)-10=0 Hint: let x= square root of u, so x squared = u
Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
u-3sqrt(u)-10=0
u-10=3sqrt(u)
u^2-20u+100=9u square each side.
u^2-29u+100=0
(u-25)(u-4)=0
u=25, u=4
u=25 is the only answer. If you check u=4 you will find that it is extraneous.
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Ed