CBSE Class 10 Mathematics Basic 2025: question 23
Set in the CBSE Class 10 board exam of 2025, paper 430/3/1, section B, question 23, for 2 marks. Try it first; the hints and our step-by-step solution are below.
Q23 · 2 marks · Very short answerCircles
In the given figure, TP and TQ are two tangents. If , then find the measure of .
Figure in the paper: A circle with centre O; external point T with tangents TP and TQ touching the circle at P and Q. Chord PQ is drawn, and angle PTQ = 50° is marked at T. Angle OPQ is marked at P between PO and PQ. See it in the official paper.
Source: official question paper from cbse.gov.in (PDF). See it in the full 2025 board paper, set 430/3/1.
Hints
Open one hint at a time and try again before the next.
Hint 1
Triangle TPQ has two equal sides. Why?
Hint 2
Find ∠TPQ first, then use the angle between a radius and a tangent.
Step-by-step solution
Each step shows the marks it earns, as an examiner would award them. Checked by an independent re-solve from the question paper.
- ½ mark
[tangents drawn from an external point are equal]. So [angles opposite equal sides].
- 1 mark
In : , so .
- ½ mark
[tangent ⟂ radius at the point of contact]. So .
Answer: ∠OPQ = 25°
Where the marks are
- Uses TP = TQ to get ∠TPQ = ∠TQP (½ mark)
- Finds ∠TPQ = 65° from the angle sum of the triangle (1 mark)
- Uses OP ⟂ TP to get ∠OPQ = 25° (½ mark)
Revise the chapter
- Chapter: Circles (notes, formulas, where marks are lost and every past question)
- Topic: Solving Problems Using Tangent Properties
More questions from Circles
- 2025 board paper, set 430/3/1 (Basic), Q31 · 3 marksIn the given figure, a circle is inscribed in a quadrilateral ABCD which touches the sides AB, BC, CD and DA a…
- 2025 board paper, set 430/4/1 (Basic), Q24(a) · 2 marksProve that the angle between the two tangents drawn from an external point to a circle is supplementary to the…
- 2025 board paper, set 430/4/1 (Basic), Q24(b) · 2 marksProve that the tangents drawn at the ends of a diameter of a circle are parallel.
The question is transcribed from the official paper; figures are described in words. The solution, hints and chapter tag are ours. Spotted an error? Write tosupport@questionbuddy.in.