REVISION NOTES
IGCSE Edexcel Mathematics A
4.1 Angles, Lines and Triangles
4.1.1 Distinguish between acute, obtuse, reflex and right angles
4.1.2 Use angle properties of intersecting lines, parallel lines and angles on a straight line
4.1.3 Understand the exterior angle of a triangle property and the angle sum of a triangle property
4.1.4 Understand the terms ‘isosceles’, ‘equilateral’ and ‘right-angled triangles’ and the angle properties of these triangles