Illustration of a circle with diameter AB. Radii are RO, SO, AO, and BO. ED is a chord.
Illustration of a circle with diameter BC, chord DF, secant MN, and tangent HK.
Illustrations of a circle with secant AD and line BC tangent to it.
Illustration showing angles formed by two secants, two tangents, or a tangent and a secant, drawn to…