Two Tangents, One Angle

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Two Tangents, One Angle

CBSE Class 10 · Solve it one decision at a time. A wrong pick earns a nudge, never the answer.

Step 1 of 3

The problem

From an external point PP, tangents PAPA and PBPB are drawn to a circle with centre OO. If ∠APB=70∘\angle APB = 70^\circ, find ∠OAB\angle OAB.

Step 1 · Your move

Tangents from one external point are equal, so triangle PABPAB is isosceles with PA=PBPA = PB. What is ∠PAB\angle PAB?

70°OPAB
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