Illustration of a circle used to prove "Any angle inscribed in a segment less than a semicircle is an…

Design made by drawing one large circle and then three circles that are internally tangent to the original…

Design made by drawing one large circle and then three circles that are internally tangent to the original…

Design made by drawing one large circle and then four circles that are internally tangent to the original…

Design made by drawing one large circle and then four circles that are internally tangent to the original…

Design made by drawing one large circle and then two circles that are vertically placed and internally…

Circular design made by rotating circles about a fixed point. The radii of the smaller circles is equal…

Circular design made by rotating circles about a fixed point. The radii of the smaller circles is equal…

The Italian Renaissance lunette panel is a semi-circle design found on a door-head.

Wrought-iron grill lunette panel. Its a semi-circle design typically found on a door-head.

Illustration of a circle used to prove "Any angle inscribed in a semicircle is a right angle."

An illustration of a right triangle inscribed in a semicircle.

Illustration of a sphere generated by the revolution of a semicircle ACB about its diameter AB as an…