Answer:
-7
Step-by-step explanation: When a= 5, let's substitute all a's with 5 in the expression:
[tex]\frac{a^{2}-4 }{a+2}\\\frac{(-5)^{2}-4 }{-5+2}\\\\\frac{25-4}{-3}\\\frac{21}{-3} \\= -7[/tex]
