I have two problems...

$\displaystyle ({{x+5}\over{x}})^{1\over2}+4({{x}\over{x+5}})^{1\ over2}=4$

$\displaystyle \sqrt{3x+4}+\sqrt{x-4}=2\sqrt{x}$

My teacher said substitution is preffered, but I only seem to make it more complicated. If substitution is not possible, solve regularly.

Can you get me started? Thanks!