The area of each 30-60-90 triangle is so the area of the
triangle with the 120° vertex is twice that, or
The shaded area, then, is about 1.047 – 0.433 = 0.614. The answer is (C).
Now that you’ve reviewed all the relevant plane geometry facts and formulas,
seen some of the test makers’ favorite plane geometry situations, and learned
a few good Kaplan strategies, it’s time to put yourself to the test again. If you
were disappointed in your performance on the Plane Geometry Diagnostic
Test, here’s your chance to make up for it.
THINGS TO REMEMBER:
Five Facts about Triangles
1. Interior angles add up to 180°.