SOLUTION: -9x1/4 + x1/2 +20=0 solve equation after making appropriate substitution

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Question 353245: -9x1/4 + x1/2 +20=0
solve equation after making appropriate substitution
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
-9%2Aroot%284%2Cx%29+%2B+sqrt%28x%29+%2B20=0
Let u=root%284%2Cx%29, u%5E2=sqrt%28x%29
u%5E2-9u%2B20=0
%28u-4%29%28u-5%29=0
Two solutions,
u-4=0
u=4
highlight%28x=4%5E4=256%29
.
.
.
u-5=0
u=5
highlight%28x=5%5E4=625%29