# How do I find the area of an isosceles triangle with.a base that is 20 m long and each of the other two sides is 26 m?

##### 1 Answer

Dec 17, 2015

#### Explanation:

Use the formula

You need to find the height of the triangle, so split the isosceles into 2 right angled triangles.

So, one newly- created right angled triangle will have a base length of *half* of the original triangle, which is

The new base length of the right- angled triangle is

You know the length of the hypotenuse is

So the height of the triangle is

Substitute everything in the formula again.

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