Angle Formed by a Tangent and a Secant
How to find the measure of the angle formed by a tangent and a secant: formula, example, and its solution.
m∠[brown] = (1/2)(m[blue arc] - m[green arc])
∠[brown]: Angle formed by a tangent and a secant
[blue arc], [green arc]: Intercepted arcs
The brown angle is the angle
formed by a tangent and a secant.
m∠[brown] = x
The intercepted arcs are 143º and 63º.
So x = (1/2)⋅(143 - 63).
143 - 63 = 80
(1/2)⋅80 = 40
So x = 40.