ΔABC and ΔDBC are on the same base BC but on opposite sides of it. AD and BC intersect each other O. If AO=a cm, DO=b cm and the area of ΔABC= x cm², then what is the area (in cm²) of ΔDBC?

The sum of all interior angles of a regular polygon is twice the sum of all its exterior angles.  The number of sides of the polygon is

The area of a circle is proportional to the square of its radius. A small circle of radius 3 cm is drawn within a larger circle of radius 5 cm. Find the ratio of the difference between the area of the larger circle and that of the smaller circle to the area of the larger circle.

An angle is four times its complementary angle. What is the measure of the angle?

In the given figure ΔDEF is right angle triangle, ∠G=120° and DG=12 cm , GF=10 cm then find out the value of DF.

In ΔPQR , ∠R=54° the perpendicular bisector of PQ at S meets QR at T. If ∠TPR =46°, then what value of (in degree) ∠PQR?

In an isosceles triangles ABC, AB=AC the median drawn on the same arms are perpendicular to each other find AB/BC?

If one of the interior angles of a regular polygon is equal to 5/6 times of one of the interior angles of a pentagon, then the no. of sides of the polygon.