Question

x+sqrt(x-4)=4

Answer 1

\[x+\sqrt{x-4}=4~~~~~~~~~~~~~~~~(\text{note the restriction, }x\ge4)\\
\sqrt{x-4}=4-x\\
\left(\sqrt{x-4}\right)^2=(4-x)^2\\
x-4=16-8x+x^2\\
x^2-9x+20=0\\
(x-5)(x-4)=0\\
~~~~~~~~~~~~~~~\vdots\]

Answer 2

wow, thank you! I can't believe I got so stuck on this one.

Answer 3

you're welcome