How to factorize 4^{n+1}+2^{2n-1}?

Question

I know the answer is 9(2^{2n-1}), but how do I get there? Step by step explanation please

Thanks

Answer 1

4^(n+1)+ 2^(2n-1)

[2^(2n-1)](2^3 +1)

= 9(2^n-1)

also

= 9(2^n)(2^-1)

= 9/2)(2^n)= 4.5(2^n)