If one angle is half of its complementary angle, find that angle.

The length of the common chord of two circles of radii 30 cm and 40 cm whose centers are 50 cm apart is (in cm) 

If AD, BE and CF are medians of ∆ABC, then which one of the following statements is correct? 

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

Find the length of a tangent, drawn to a circle of radius 4 cm, from a point which is at a distance of 5 cm from the centre?

If the perimeter of an equilateral triangle is 30 meters, what is its height?

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

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?