How do you solve 4^( x + 2) = 20?

1 Answer
May 28, 2016

I found: x=(ln(20))/(ln(4))-2=0.16096

Explanation:

I would first take the natural log of both sides:
ln(4)^(x+2)=ln(20)
then use a property of logs to write:
(x+2)ln(4)=ln(20)
rearrange:
x+2=(ln(20))/(ln(4))
and:
x=(ln(20))/(ln(4))-2=0.16096