ConstructionModerate2 marks
8(b)
Draw a line AB = 5 cm. Mark a point C on AB such that AC = 3 cm. Using a ruler and a compass only, construct :
A circle of radius 2.5 cm, passing through A and C.
Topic: Geometrical construction
Previous-year question practice database
Answer
Solution diagram

Exam answer
Construction:
- Draw AB = 5 cm.
- Mark C on AB such that AC = 3 cm.
- Construct the perpendicular bisector of AC.
- Since the required radius is 2.5 cm, take A as centre and radius 2.5 cm and draw an arc cutting the perpendicular bisector of AC at O.
- With O as centre and radius 2.5 cm, draw the circle through A and C.
Answer:
Required circle constructed.
Explanation
The centre of a circle passing through A and C must be equidistant from A and C, so it lies on the perpendicular bisector of AC. Its distance from A and C must also equal the given radius 2.5 cm.
More from Constructions (Circles)
construct an equilateral triangle ABC of side 5 cm.2026construct the circumcircle of ΔABC.2026give the geometrical name of quadrilateral ABCD2026Statement 1: The point which is equidistant from three non-collinear points D, E and F is the circumcenter of the ΔDEF.
Statement 2: The incenter of a triangle is the point where the bisector of the angles intersects.2025Use ruler and compass for the following construction. Construct a ΔABC, where AB = 6 cm, AC = 4.5 cm and ∠BAC = 120°. Construct a circle circumscribing the ΔABC. Measure and write down the length of the radius of the circle.2025Using ruler and compass construct a triangle ABC in which AB = 6 cm. ∠BAC = 120° and AC = 5 cm. Construct a circle passing through A, B and C. Measure and write down the radius of the circle.2023