Question 1141405
{{{x^(1/2)-9x^(1/4)+20=0}}}


If {{{p=x^(1/4)}}}, then {{{p^2=x^(1/4+1/4)=x^(1/2)}}};



substituting that 
{{{p^2-9p+20=0}}}

and maybe this is factorable or maybe not.  Try and see.  Otherwise, use general solution formula method.  Continue from there.










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Let {{{cross(p=x^(1/2))}}}