Knowing that logarithm functions and exponential functions are inverse to each other, the procees to convert a logarithmic equation to its equivalent is to perform all the operations to set an equation of the typ:

,
then invert to show it equivalent form:

.
With that you have solved the equation for x.
Answer:
23.5
Step-by-step explanation:
First the shaded area is 28 but there is a triangle so we have to solve the area of the triangle. (formula for triangle: B x H x 1/2) 3 times 3=9 divided by 2=4.5
28-4.5=23.5