# How do you solve  log x + log 4 = log (x + 9)?

Nov 30, 2015

Use the properties of logs ...

#### Explanation:

$\log x + \log 4 = \log 4 x = \log \left(x + 9\right)$

Next, set arguments equal to each other ...

$4 x = x + 9$

Finally, solve for x ...

$3 x = 9$

ANSWER : $x = 3$

hope that helped