The ‘legs’ are the two equal sides. The third side is called the base, even when the triangle is in a different orientation. An isosceles triangle has two angles that are the same size.

Besides, we will see how to calculate the area of a triangle, area of an equilateral triangle, area of an isosceles triangle and heron’s formula. Also check the solved examples.

Working with Sketch 6 Project Sketch 6 on the screen. Review the term equilateral (red triangle) and introduce the term isosceles (outline). Have the students predict whether the equilateral triangle ...

You'll be using Sketch 1 of this file which has three different types of triangles - scalene, isosceles, equilateral. Each triangle type has a different colour (pink for scalene, red for equilateral, ...