The measure of angle B is 93 degrees, the measure of arc BC is 72 degrees, and the measure of arc CD is 122 degrees.

What is the measure of angle C?

1 answer

To find the measure of angle \( C \), we can use the property of angles formed by two chords that intersect at a point inside a circle. The measure of an angle formed by two chords intersecting inside a circle is equal to half the sum of the measures of the arcs intercepted by the angle and its opposite angle.

Given:

  • Measure of angle \( B = 93^\circ \)
  • Measure of arc \( BC = 72^\circ \)
  • Measure of arc \( CD = 122^\circ \)

From the problem statement, we assume:

  • Arc \( BD \) is intercepted by angle \( B \)
  • Arc \( BD \) is made up of arcs \( BC \) and \( CD \)

To find the measure of angle \( C \), we first need to determine the measure of arc \( BD \):

\[ \text{Measure of arc } BD = \text{Measure of arc } BC + \text{Measure of arc } CD = 72^\circ + 122^\circ = 194^\circ \]

Now, we can calculate the measure of angle \( C \) using the formula for the measure of the angle formed by two chords:

\[ \text{Measure of angle } C = \frac{1}{2} \left(\text{Measure of arc } BD - \text{Measure of arc } BC\right) \]

Calculating the measure of angle \( C \):

\[ \text{Measure of angle } C = \frac{1}{2} \left(194^\circ - 72^\circ\right) = \frac{1}{2} \cdot 122^\circ = 61^\circ \]

Therefore, the measure of angle \( C \) is \( \boxed{61^\circ} \).