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Mathematics — CBSE Class 10 board question

Q1. [1]
In the given figure, $AB$ and $AC$ are tangents to the circle. If $\angle ABC = 42°$, then the measure of $\angle BAC$ is :
  1. A 96°
  2. B 42°
  3. C 106°
  4. D 86°
Previously asked in CBSE board exam
2024 30/4/1 Q15
Generated by claude-sonnet-4-6 · 2026-06-15 10:23 · grounding rag
Model Answer

Since AB and AC are tangents from external point A, triangle ABC is isosceles with AB = AC, so ∠ACB = ∠ABC = 42°.
∠BAC = 180° − 42° − 42° = 96°. → Option A

Explanation

Equal tangents from an external point (Theorem 10.2) make △ABC isosceles, so base angles ∠ABC = ∠ACB = 42°. Apply angle sum: 180° − 84° = 96°. Watch for this standard isosceles-tangent triangle setup in MCQs.

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