Chapter 9 - Test - Page 599: 18

$x=\dfrac{\log4-5\log3}{2\log3} \\\\ x\approx-1.8691 $

Getting the logarithm of both sides, then, \begin{array}{l} 3^{2x+5}=4 \\\\ \log3^{2x+5}=\log4 \\\\ (2x+5)\log3=\log4 \\\\ 2x\log3+5\log3=\log4 \\\\ 2x\log3=\log4-5\log3 \\\\ x=\dfrac{\log4-5\log3}{2\log3} \\\\ x\approx-1.8691 .\end{array}