STEP - BY - STEP EXPLANATION
What to find?
Determine if the student is correct with the solution -2.
Given:
To solve, we will follow the steps below:
Step 1
Determine the LCM.
The LCM in this case is a² - 4 which is the same as (a+2)(a-2).
Step 2
Multiply through by (a+2)(a-2)

Step 3
Open the parenthesis.

Step 4
Collect like term.

Step 5
Simplify.

Step 6
Divide both-side of the equation by -4


ANSWER
The solution is -2 . Hence the student is correct.