Angle Rules
Maths: Edexcel IGCSE Higher, topic 4.1.2
Angle Rules
Angles at a point on one side of a straight line add up to 180°
Angles around a point add up to 360°
Angles in Parallel Lines
When a line crosses a pair of parallel lines, there are a number of relations between pairs of angles:
General case
Alternate angles are the same
Allied or cointerior angles add up to 180°
- a + b = 180°
Corresponding angles are the same
Opposite angles are the same
Test yourself on Angle Rules
What do angles around a point add up to?
What do angles on a line add up to?
If x = 60°, what is y?
If x = 60°, what is y?
If x = 60°, what is y?