The graph of shows the value of the common logarithm for different -values. To find the value of you read the -value where -value is equal to , from the graph.
Since the point is placed on the -axis, the -value is
When we solve the equation we know the value of the common logarithm, and instead find the -value which gives the -value equal to . We start at the -value of go out to the graph and down to the -axis, where we read the -value from the axis.
Here we will rewrite the equation according to the common logarithm's definition, As in the first part, find the value of by reading what -value is when the -value is equal to
We see that is approximately equal to