(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Solve [tex]x-\sqrt{x}-6=0[/tex]

2. Relevant equations

3. The attempt at a solution

This can be factorised into [tex](\sqrt{x}-3)(\sqrt{x}+2)=0[/tex]

so [tex]\sqrt{x}=3[/tex] , x=9 .

[tex]\sqrt{x}=-2[/tex] ... Why is this root not acceptable ?

I recalled that if

[tex]x^2=4[/tex] , then [tex]x=\pm 2[/tex]

but if [tex]x=\sqrt{4}[/tex] , then x=2

Is this true ?

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# Homework Help: Solving an equation

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