Question

Solve the equation. Round to the nearest hundredth. Show work.

$5^{-2x-1} = 4^{4x+3}$

Answer 1

Answer:

Final answer is approx x=-0.66.

Step-by-step explanation:

Given equation is $5^{-2x-1}=4^{4x+3}$.

Now we need to solve equation $5^{-2x-1}=4^{4x+3}$ and round to the nearest hundredth.

$5^{-2x-1}=4^{4x+3}$

$\log(5^{-2x-1})=\log(4^{4x+3})$

$(-2x-1)\log(5)=(4x+3)\log(4)$

$-2x \log(5)- \log(5)=4x \log(4)+3 \log(4)$

$-2x \log(5) -4x \log(4)=3 \log(4) +\log(5)$

$x=\frac{\left(3\log(4)+\log(5)\right)}{\left(-2\log(5)-4\log(4)\right)}$

Now use calculator to calculate log values, we get:

$x=-0.65817959094$

Round to the nearest hundredth.

Hence final answer is approx x=-0.66.