Question

A chord of length 12 cm subtends an angle of 78.2 degree at the center of a circle. Find the radius of the circle. The best solution will be marked as brainliest

Answer 1

Answer:

The 78.2 degrees at the center means that the sum of the other angles is 180 - 78.2, or 101.8 degrees.

The other two angles are equal to each other.

Each angle is 101.8/2, which is 50.9 degrees.

Opposite each of those 50.9 angles there is a radius of the circle.

Using the Law of Sines:

sine 78.2* is to 12 cm as sine 50.9* is to radius.

.98/ 12= .78/ r

12 (.78) = .98 r

r = 9.55 cm