How do you solve e^(3-5x)=16?

1 Answer
Apr 20, 2018

color(blue)(x=(ln(16)-3)/-5~~0.0454822555)

Explanation:

By the laws of logarithms:

log_a(b^c)=clog_a(b) \ \ \ \ \ [1]

log_a(a)=1 \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ [2]

e^(3-5x)=16

Taking natural logarithms of both sides:

Using [1]

(3-5x)ln(e)=ln(16)

By [2]

3-5x=ln(16)

Subtract 3:

-5x=ln(16)-3

Divide by -5:

color(blue)(x=(ln(16)-3)/-5~~0.0454822555)