PLEASE CHECK MY ANSWERS

Question

1. Write f(x)=4^x-3 in f(x)=ab^x
F(x)=(1/64)(4)^x

2.solve for x 4^x+2=3^x-5
X=-log4/3(3888)

3.solve for x
Log5(x+4)+log5(8)=log8(64)
X=-7/8

Answer 1

#1 ok

#2. almost. It is actually
-log(3888) / log(4/3)

#3. ok