Let's solve the original equation again, step by step, to find out which of the provided answers is correct.
The equation is:
\[
7^{3x} + 8 = 49
\]
- Subtract 8 from both sides:
\[
7^{3x} = 49 - 8
\]
\[
7^{3x} = 41
\]
At this point, we realized \( 7^{3x} = 41 \) doesn't directly suggest a simple solution in terms of recognizing the powers of \( 7 \). However, let’s manipulate the equation without misunderstanding.
- Use logarithms to solve for \( x \):
Take logarithm base 7 of both sides:
\[
3x = \log_7(41)
\]
Or take natural logarithms (or common logarithms):
\[
3x = \frac{\log(41)}{\log(7)}
\]
\[
x = \frac{1}{3} \cdot \frac{\log(41)}{\log(7)}
\]
Since \(\log(41)\) and \(\log(7)\) give a specific value, but we want to determine which of the options provided corresponds in terms of rational values.
Let's analyze the proposed answers:
- \( x = 3 \)
- \( x = -2 \)
- \( x = -\frac{7}{3} \)
- \( x = -\frac{6}{7} \)
None of these are derived directly from the equation we derived. However, let's compare the calculated values approximately.
Using logarithms (digital calculations may yield clearer results) provides:
- \( x \approx 0.636 \) (from \( 7^{3x} = 41 \))
Upon reviewing the possible answers:
To check if any of these answers can be a solution:
-
If we substitute \( x = -2 \):
\[
7^{3(-2)} + 8 = 7^{-6} + 8 \approx 0 + 8 \neq 49
\]
-
If we substitute \( x = 3 \):
\[
7^{3(3)} + 8 = 7^9 + 8 \gg 49
\]
-
\( x = -\frac{7}{3} \) and \( x = -\frac{6}{7} \) also produce results that do not satisfy \( 7^{3x} + 8 = 49 \).
From this close evaluation, I couldn't find a compatible match directly from the computed logarithm and provided options:
The derived \( 7^{3x} = 41 \) does indeed show that no option satisfies satisfactorily.
If you wish for simplified clarity or strategy in reaching powers of 7 equations, also feel free to ask anything specific! Thank you for your patience!