# Area of triangles: triangles with a right angle

Learning Material  |  Interactive Lesson

Description
Find the area of right-angled triangles. Explore how the formula works. First, estimate the area of a chosen triangle on a grid. Next, work out the correct formula by assembling a series of triangles and rectangles. Then, compare the actual area of the triangle with your original estimate. Practise applying the formula directly to a range of right-angled triangles. This learning object is one in a series of four objects.
Objective
1. Students estimate the area of triangles.
2. Students identify the base and height pairs of right-angled triangles, including the base-height pair formed by the perpendicular sides of the triangle.
3. Students identify the relationship between area of triangles and rectangles.
4. Students establish that all three base-height pairs can be used to calculate the area of triangles.
5. Students identify and apply the correct formula for calculating the area of a triangle.