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AC is tangent to circle O at A. The Diagram is not to scale.

If mBY = 52 what is YAC?
I know the answer is B) 64, But Can someone show me the work?

AC is tangent to circle O at A. The Diagram is not to scale. If mBY = 52 what is YAC-example-1
User Calmrat
by
5.1k points

2 Answers

6 votes

Answer:

m∠BAY = 1/2(52°) = 26°

m∠BAC = 90°

m∠YAC = m∠BAC - m∠BAY

m∠YAC = 90° - 26° = 64°

OAmalOHopeO

User Steve Homer
by
3.9k points
4 votes

Answer:

  • B. 64°

Explanation:

Given:

  • mBY = 52°

Inscribed angle measure is half the intercepted arc:

  • m∠BAY = 1/2(52°) = 26°

The angle between the diameter and tangent is right angle:

  • m∠BAC = 90°

According to angle addition postulate:

  • m∠YAC = m∠BAC - m∠BAY
  • m∠YAC = 90° - 26° = 64°

Correct choice is B

User Tad
by
4.9k points