Find the value of ∠BAC in the given diagram If AB=AC=CD and ∠ADB=20°?

Inside a square PQRS, ΔQTR is an equilateral triangle. If RT and QS intersect at O, then ∠QOR is equal to-

The midpoints of AB and AC of a triangle ABC are X and Y respectively. If BC + XY = 12 units, then BC – XY is:

What is the measure of the circum radius of a triangle whose sides are 9cm, 40cm and 41cm?

If the angles of a triangle are in the ratio of 2:3:7, then find the ratio of the greatest angle to the smallest angle.

In triangle ABC, AD, BE and CF are the medians intersecting at point G and area of triangle ABC is 156 cm². what is the area (in cm²) of triangle FGE? 

If the angles of a triangle are in the ratio of 1:4:7, then find the ratio of the greatest angle to the smallest angle.

The centroid of a ∆ABC is G. The area of ∆ABC is 60 cm². The area of ∆GBC is