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Solving exponential and logarithmic equations

Answer Text:
Solving exponential and logarithmic equations
By taking logarithms, and exponential equation can be converted to a linear equation and solved. We will use the process
of taking logarithms of both sides.
Note:
A logarithmic expression is defined only for positive values of the argument. When we solve a logarithmic equation it is essential to verify that the
solution(s) does not result in the logarithm of a negative number.
Solutions that would result in the logarithm of a negative number are called extraneous, and are not valid solutions.
Example 1.
Solve for x.
#4^x = 12#
Example 2.
Solve for x:
#log_5(x+1) + log_5(x-3)=1#
Example 3.
Solve the equation
#10^x = 3.79#