Question 867263
Question (a)  looks like the more complicated one.


{{{log(5,(x^2-4))-log(5,4)=log(5,3)}}}
{{{log(5,((x^2-4)/4))=log(5,3)}}}
The inputs are to the same base, and so must be equal.
{{{(x^2-4)/4=3}}}
{{{x^2-4=12}}}
{{{x^2=16}}}
{{{x=0+- 4}}}