Solve for x
x=-\frac{1}{2}=-0.5
Solve for x (complex solution)
x=-\frac{i\pi n_{1}}{\ln(7)}-\frac{1}{2}
n_{1}\in \mathrm{Z}
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49^{-x}=7
Calculate 7 to the power of 2 and get 49.
\log(49^{-x})=\log(7)
Take the logarithm of both sides of the equation.
-x\log(49)=\log(7)
The logarithm of a number raised to a power is the power times the logarithm of the number.
-x=\frac{\log(7)}{\log(49)}
Divide both sides by \log(49).
-x=\log_{49}\left(7\right)
By the change-of-base formula \frac{\log(a)}{\log(b)}=\log_{b}\left(a\right).
x=\frac{\frac{1}{2}}{-1}
Divide both sides by -1.
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