Answer:
90
Step-by-step explanation:
Given: Measure of one side of equilateral triangle = 
Measure of another side of equilateral triangle = 
In equilateral triangle all three sides are equal in length.Therefore,




On substituting the value of x in side of equilateral triangle,
One side of equilateral triangle = 
Perimeter of equilateral triangle = 3 ( length of one side) ........( given)
perimeter of equilateral triangle = 
For this case we have the following functions:

The first thing we must do for this case is to subtract both functions.
We have then:

Substituting we have:

Rewriting we have:

Evaluating the obtained function for x = 3 we have:

Answer:
The value of the function evaluated at x = 3 is:
