Answer :

W0lf93
We have to find the measure of Angle BCA if line AD is a tangent to circle B. Then we have to choose the correct answer. Tangent line is a line that touches a circle at exactly 1 point. The tangent line ( here AD ) at point C is perpendicular to the radius ( here BC ) to that point. Therefore measure of Angle BCA is 90°. Answer: C. 90°.

Answer: 90

Step-by-step explanation: They are correct. I got it right on the test. Just confirming the answer.