Answer
$\log{(xy^7)}$
Work Step by Step
RECALL:
(1) $\log{a}-\log{c} = \log{(\frac{a}{c})}$
(2) $\log{a} + \log{c} = \log{ac}$
(3) $a \cdot \log{x} = \log{x^{a}}$
Use rule (3) above to obtain:
$=\log{x}+\log{(y^7)}$
Use rule (2) above to obtain:
$=\log{(xy^7)}$
