How do you find the inverse of y=log_5(x+4)+1y=log5(x+4)+1?

1 Answer
Nov 30, 2015

I found: y=5^(x-1)-4y=5x14

Explanation:

I would try to isolate xx on one side by first moving 11 and then changing the log into an exponential as:
log_5(x+4)=y-1log5(x+4)=y1
x+4=5^(y-1)x+4=5y1
x=5^(y-1)-4x=5y14

Now I switch places to give it a more "friendly-function" aspect:
y=5^(x-1)-4y=5x14

Graphically you have:
y=log_5(x+4)+1y=log5(x+4)+1 (red)
y=5^(x-1)-4y=5x14 (blue)

enter image source here