Geometrical Constructions questions with worked answers for Cambridge IGCSE Mathematics (0580). Each question says whether it is Core or Extended and whether it is for a calculator or non-calculator paper. Try each one before you open the answer.
4.2 Geometrical constructionsCore Measure and draw lines and angles; Construct a triangle from three sides with a ruler and compasses only, showing the construction arcs; Draw, use and interpret nets; Perpendicular and angle bisector constructions and loci are not required.
Summarised in our own words: check the exact wording in the official 0580 syllabus.
Geometrical Constructions questions: Core
For everyone: Core students (Papers 1 and 3) and Extended students (Papers 2 and 4).
Question 1 Core non-calculator · easy
You are constructing a triangle with sides \(7\) cm, \(5\) cm and \(4\) cm, using a ruler and compasses only. You draw the \(7\) cm side first. What radius do you set the compasses to for the arc from each end?
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The other two sides are \(5\) cm and \(4\) cm.
Draw an arc of radius \(5\) cm from one end and an arc of radius \(4\) cm from the other. Where they cross is the third corner.
Answer: \(5\) cm from one end and \(4\) cm from the other
Question 2 Core non-calculator · easy
(a) How many squares are in the net of a cube? (b) Which shapes make the net of a square-based pyramid?
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(a) A cube has \(6\) square faces.
(b) One square base and \(4\) triangles.
Answer: (a) \(6\) (b) \(1\) square and \(4\) triangles
Question 3 Core non-calculator · easy · 1 mark
A net is made from 2 triangles and 3 rectangles. Write down the name of the solid it folds to make.
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B1 (triangular) prism
Answer: triangular prism
Question 4 Core non-calculator · medium
Can a triangle be constructed with sides \(3\) cm, \(4\) cm and \(8\) cm? Give a reason.
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The two arcs only meet if the two shorter sides together are longer than the longest side.
\(3 + 4 = 7\), which is less than \(8\), so the arcs do not meet.
Answer: No, because \(3 + 4 \lt 8\)
Question 5 Core non-calculator · medium
The net of a triangular prism is drawn. How many rectangles and how many triangles does it have?
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A triangular prism has \(2\) triangular ends and \(3\) rectangular faces.
Answer: \(3\) rectangles and \(2\) triangles
Question 6 Core non-calculator · medium
A cuboid measures \(5\) cm by \(3\) cm by \(2\) cm. Work out the total area of its net.
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The net has two of each face: \(5 \times 3 = 15\), \(5 \times 2 = 10\), \(3 \times 2 = 6\).
\(2(15 + 10 + 6) = 62\) cm²
Answer: \(62\) cm²
Question 7 Core non-calculator · medium · 3 marks
Using a ruler and compasses only, construct triangle \(ABC\) with \(AB = 8\) cm, \(BC = 6\) cm and \(AC = 5\) cm. Leave in your construction arcs. Then measure the largest angle of the triangle.
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B1 AB drawn 8 cm (±2 mm)
B1 arcs radius 6 cm from B and 5 cm from A, intersecting at C
B1 largest angle, at C, 93° (accept 92° to 94°)
Answer: triangle with construction arcs; angle \(ACB \approx 93^\circ\)
Question 8 Core non-calculator · hard
A triangle is constructed with sides \(6\) cm, \(8\) cm and \(10\) cm. Without measuring, find the size of its largest angle.
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\(6^2 + 8^2 = 36 + 64 = 100 = 10^2\).
By the converse of Pythagoras' theorem, the angle opposite the \(10\) cm side is a right angle.
Answer: \(90°\)
Question 9 Core non-calculator · hard · 3 marks
The net of a closed cylinder is two circles of radius 3 cm and a rectangle. The height of the cylinder is 10 cm.
(a) Find the length of the rectangle. Give your answer in terms of \(\pi\).
(b) Find the total area of the net. Give your answer in terms of \(\pi\).
Every question on this page is original, written for IGCSE Math Revision rather than taken from Cambridge papers, and each answer was re-solved independently before publishing. Questions with a mark scheme come from our 0580 practice bank (M method, A accuracy, B independent marks).
Which Cambridge 0580 papers can test geometrical constructions?
Geometrical Constructions is on both tiers (syllabus 4.2), so it can come up on Core Papers 1 (non-calculator) and 3 (calculator), and Extended Papers 2 (non-calculator) and 4 (calculator). Extended candidates also need the Extended parts listed on this page. Half of each tier's marks are on a non-calculator paper, so practise the non-calculator questions without one.
Are these Cambridge past-paper questions?
No. Every question here was written for IGCSE Math Revision in the style of the 0580 papers, and each answer was checked independently before publishing. For real exam practice, use the Cambridge past papers linked from our 0580 past papers page.
Where can I practise more geometrical constructions questions?
In the 0580 practice for topic 4 (Geometry), where every question is marked and tagged Core or Extended. Practice is part of the IGCSE plan, with a free preview; the questions on this page are free.