The measure of an angle is 13°. What is the measure of its complementary angle?

77°

Step-by-step explanation:

Complementary angles formula

90°- x°. (X is the given angle)

So,

90°-13°

= 77°

answer: option a.

step-by-step explanation:

you know that the quadrilateral opqr ( a four sided figure) is inscribed in circle. this means that all its vertices are on the circle.

then, by definition, the opposite angles of the quadrilateral are supplementary, this means that the sum of their measures is 180 degrees.

you can observe in the figure that the angles ∠opq   and the angle ∠orq   are opposite, therefore:

then, can be used to d to calculate the measure of ∠opq