## College Algebra 7th Edition

(a) $x=\dfrac{\ln{8}}{0.4}$ (b) $x \approx 5.198604$
(a) Take the natural logarithm of both sides to obtain: $\ln{e^{0.4x}} = \ln{8}$ Use the rule $\ln{e^n} = n$ to obtain: $0.4x = \ln{8} \\\dfrac{0.4x}{0.4}=\dfrac{\ln{8}}{0.4} \\x=\dfrac{\ln{8}}{0.4}$ (b) Use a calculator to evaluate the answer and have: $x \approx 5.198604$