Link to the May 2017 Brain Puzzler Solution:
April’s Brain Puzzler
What is the area of the shaded region of the given 8 x 5 rectangle?
What is the area of the shaded region of the given 8 x 5 rectangle?
The area is 6.5 square units.
Using extra lines to break the shape into triangles is a great way to solve this problem.
https://artofproblemsolving.com/wiki/index.php/2016_AMC_10A_Problems/Problem_11