# How do you solve e^(3r)+4=59?

Jan 28, 2017

$r = \ln \frac{55}{3} = 1.336$

#### Explanation:

${e}^{3 r} + 4 = 59$ can be rewritten as ${e}^{3 r} = 59 - 4 = 55$

As "$\ln$" is natural logarithm to the base $e$,

by taking logarithm of both sides to base $e$,

we get $\text{ } 3 r = \ln 55$ and

$r = \ln \frac{55}{3} = \frac{4.00733}{3} = 1.33578$ or $1.336$

(using scientific calculator)