## College Algebra (11th Edition)

$x\approx-13.257$
$\bf{\text{Solution Outline:}}$ To solve the given equation, $6^{x+3}=4^x ,$ take the logarithm of both sides. Then use the laws of logarithms to isolate the variable. Express the answer with $3$ decimal places. $\bf{\text{Solution Details:}}$ Taking the logarithm of both sides, the equation above is equivalent to \begin{array}{l}\require{cancel} \log6^{x+3}=\log4^x .\end{array} Using the Power Rule of the laws of exponents which is given by $\left( x^m \right)^p=x^{mp},$ the equation above is equivalent to \begin{array}{l}\require{cancel} (x+3)\log6=x\log4 .\end{array} Using the Distributive Property which is given by $a(b+c)=ab+ac,$ the expression above is equivalent to \begin{array}{l}\require{cancel} x\log6+3\log6=x\log4 .\end{array} Using the properties of equality to isolate the variable results to \begin{array}{l}\require{cancel} x\log6-x\log4=-3\log6 \\\\ x(\log6-\log4)=-3\log6 \\\\ x=\dfrac{-3\log6}{\log6-\log4} \\\\ x\approx-13.257 .\end{array}