Q. 121

# Each of the two equal angles of an isosceles triangle is four times the third angle. Find the angles of the triangle.

Answer :

Given: Each of the two equal angles of an isosceles triangle is four

times the third angle

**Formula Used/Theory:-**

→ Angle sum property

Sum of all angles of triangle is 180°

Let the 3^{rd} angle be X

The other 2 angle will be

4X

⇒ By angle sum property

X + 4X + 4X = 180°

9X = 180°

X = = 20°

The angles of triangle will be 4×20°;4×20°;1×20°

The angles of triangle is 80°;80°;20°

**Result:-** The angles of triangle is 80°;80°;20°

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