Problem 45338. Area-04

Asif, Thanks for another nice problem.
I think the description would be improved if it said the "red shaded portion", because there are two shaded portions in the drawing.

@ChrisR Going by the test suite I think the illustration should actually look like this:

clear variables
close all
[a, b] = deal(7, 2);
rectangle("Position", [-a/2 0 a b])
rectangle("Position", [-a/2 0 a/2 b], "FaceColor", "red")
rectangle("Position", [ -b 0 b b], "Curvature", [1 1], "FaceColor", "white")
rectangle("Position", [ 0 0 b b], "Curvature", [1 1])
axis equal
set(gca, "XTick", [], "YTick", [], "XColor", "w", "YColor", "w")

You're right, Christian. Thanks for correcting my comment, which I deleted.