Answer:

Step-by-step explanation:
Consider irght triangle PRS. By the Pythagorean theorem,

Thus,

Consider isosceles triangle MSC. In this triangle

The area of this triangle is

Consider right triangle PTS. The area of this triangle is

The area of the quadrilateral PMCT is the difference in area of triangles PTS and MSC:

An equilateral triangle has 3 congruent sides so the 2 expressions above are equal
3x - 9= 23 - 5x
And then you solve for x
-22=-2x
X=11
The sum of the two is three over ten or 3/10
It is proportional because all the sides are equal.