In a polygon, the sum of the interior angles is double the sum of the exterior angles. What is the number of sides of the polygon?

The Median of an isosceles triangle ΔABC is AD and ∠A = 110 °, AB = AC, find the value of ∠ADB.

Two medians AD and BE of ∆ABC intersect G at right angle. If AD = 9 cm and BE = 6 cm, then the length of BD ( in cm ) is

 If $$ {x=7-4\sqrt{3}}$$ find the value of $$ {\sqrt{x}+{1\over {\sqrt{x}}}}$$.

Two equal circles of radius 4 cm intersect each other such that each passes through the center of the other. The length of the common chord is

In ΔABC, AB = AC and ∠B = 40 °, find the value of ∠A.

In a triangle ΔABC, the sides DE parallel to BC and AD = 6 cm, DB = 9 cm, AE = 8 cm, find the value of AC.

A circle and a rectangle have the same perimeter. The sides of the rectangle are 18 cm and 26 cm. The area of the circle is: