In the diagram below, AB is the chord of a circle with centre O. OM is perpendicular to AB (meet at a right angle). Look at triangles OAM and OBM. The hypotenuses (OA and OB) are the same, as they are ...

The four triangular pieces of two models denoted by MA.304723.755 and MA.304723.760 may be arranged to form a parallelogram (in two ways) and a triangle (in two ways), constituting a partially hinged ...

The secret to getting ahead is getting started. In the triangle above, segment BD is an angle bisector. Sides AB = 9x − 14, BC = 4x − 3, CD = 2x + 11 and AD = 5x + 2. Find the area of triangle ABD and ...

This section deals with 2D shapes and angles related to them. It might be worth looking at the National 4 Angles section before continuing. For any triangle, the three angles add up to \(180^\circ\).