### Home > CCA2 > Chapter 7 > Lesson 7.1.5 > Problem7-80

7-80.

Solve each of the following equations.

Since $x$ is in the exponent, start by taking the log of both sides.

1. $5^x=72$

$x\approx2.657$

1. $2^{3x}=7$

$\log(2)^{3x} = \log(7)$

$3x \cdot \log(2) = \log(7)$

$3x = \frac{\log (7)}{ \log (2)}$

Use your calculator and continue solving the equation.

1. $3^{(2x+4)}=17$

$x\approx−0.711$