Bunuel

In square PQRS above, QR = 1, RU = US, and PT = TS. What is the area of the quadrilateral PRUT?
(A) 1/8
(B) 1/4
(C) 3/8
(D) 5/8
(E) 2/3
Attachment:
2017-10-11_1127.png
\((Area_{square}) - (Area_{2triangles}) = (Area_{quad})\)Square side length = 1
Top triangle legs' length = 1
Bottom triangle legs' length* = \(\frac{1}{2}\)
Area of square: \(s^2 = 1^2 = 1\)
Area of top triangle: \(\frac{s^2}{2}=\frac{1}{2}\)
Area of bottom triangle: \(\frac{s^2}{2} \\
=\frac{(\frac{1}{4})}{2} = \frac{1}{8}\)
Both triangles' area:
\(\frac{1}{2} + \frac{1}{8} = \frac{5}{8}\)
Quadrilateral area: \(1 - \frac{5}{8}=\frac{3}{8}\)
Answer C
*
The segments that constitute the legs of this right triangle are both \(\frac{1}{2}\) the length of the side of the square because they are half of a bisected side.
Square side RS is bisected; we are given that RU = US. Square side PS is similarly bisected.