Questions: Solve the exponential equation. Round to three decimal places when needed.
5(0.8^x)=4
x=
Transcript text: Solve the exponential equation. Round to three decimal places when needed.
\[
5\left(0.8^{x}\right)=4 \\
x=
\]
Solution
Solution Steps
To solve the exponential equation \(5(0.8^x) = 4\), we first isolate the exponential term by dividing both sides by 5, resulting in \(0.8^x = \frac{4}{5}\). Next, we take the logarithm of both sides to solve for \(x\). Using the property of logarithms that \(\log(a^b) = b \log(a)\), we can solve for \(x\) by dividing the logarithm of the right side by the logarithm of 0.8.
Step 1: Isolate the Exponential Term
Starting with the equation:
\[
5(0.8^x) = 4
\]
we divide both sides by 5:
\[
0.8^x = \frac{4}{5}
\]
Step 2: Apply Logarithms
Next, we take the logarithm of both sides:
\[
\log(0.8^x) = \log\left(\frac{4}{5}\right)
\]
Using the property of logarithms, we can rewrite the left side:
\[
x \log(0.8) = \log\left(\frac{4}{5}\right)
\]
Step 3: Solve for \(x\)
Now, we solve for \(x\) by dividing both sides by \(\log(0.8)\):
\[
x = \frac{\log\left(\frac{4}{5}\right)}{\log(0.8)}
\]
Calculating this gives:
\[
x \approx 1.0
\]
Final Answer
Thus, the solution to the equation is:
\[
\boxed{x = 1.0}
\]