Question 1
Two angles on a straight line are \(3x\) and \(2x\).
Find \(x\).
Show the worked answer
- Angles on a straight line add to \(180°\): \(5x = 180\).
Answer: \(x = 36\)
Cambridge IGCSE Maths (0580) · Topic 4: Geometry · 4.6
Angles 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.
Summarised in our own words: check the exact wording in the official 0580 syllabus.
For everyone: Core students (Papers 1 and 3) and Extended students (Papers 2 and 4).
Two angles on a straight line are \(3x\) and \(2x\).
Find \(x\).
Answer: \(x = 36\)
Two angles of a triangle are \(47°\) and \(68°\).
Find the third angle.
Answer: \(65°\)
A regular polygon has 10 sides. Find
(a) the size of each exterior angle (b) the size of each interior angle.
Answer: (a) \(36^\circ\) (b) \(144^\circ\)
Work out the size of
(a) each exterior angle
(b) each interior angle
of a regular octagon.
Answer: (a) \(45°\) (b) \(135°\)
A regular polygon has exterior angles of \(20°\).
How many sides does it have?
Answer: \(18\)
Work out the sum of the interior angles of a heptagon (\(7\) sides).
Answer: \(900°\)
Two parallel lines are crossed by a straight line. One of the angles formed is \(64^\circ\). Find
(a) the angle corresponding to it (b) the angle co-interior to it.
Answer: (a) \(64^\circ\) (b) \(116^\circ\)
Five of the interior angles of a hexagon are \(110^\circ\), \(125^\circ\), \(130^\circ\), \(118^\circ\) and \(102^\circ\). Find the sixth angle.
Answer: \(135^\circ\)
The interior angles of a pentagon are \(x°\), \(2x°\), \(100°\), \(110°\) and \(120°\).
Find \(x\).
Answer: \(x = 70\)
A line crosses two parallel lines. Two co-interior angles are \((2x + 10)°\) and \((3x - 30)°\).
Find \(x\).
Answer: \(x = 40\)
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).
Angles is on both tiers (syllabus 4.6), 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.
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.
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.