Question

How do you solve this question

Answer 1

$a - 4 = ( \sqrt{a} - 2)( \sqrt{a} + 2)$

$\frac{ \sqrt{a} - 2}{a - 4} = \frac{ \sqrt{a} - 2}{( \sqrt{a} - 2)( \sqrt{a} + 2) } = \frac{1}{ \sqrt{a} + 2 }$