This shape is important in the future study of the circle, because of its characteristic of having two sides the same length.
In this diagram, a = b. Be sure to direct your childs attention to the double line symbol under a and b. This is a standard method of indicating lines that are the same length in polygons.
Also, the base angles are indicated using the same symbol (any symbol can be used), as they are also equal.
The area of an Triangle which is Isosceles is calculated in the same manner as ANY triangle. This is covered in our Right Triangle section.
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