In any triangle ABC, AB + BC = 12 cm, BC + CA = 14 cm and CA + AB = 18 cm. What will be length of radius of a circle, if the perimeter of circle is equal to the perimeter of triangle ABC? 

Two circles intersect at A and B, P is a point on produced BA. PT and PQ are tangents to the circles. The relation of PT and PQ is 

For an equilateral triangle, the ratio of the in-radius and the outer- radius is

Triangle PQR is such that PQ=9 cm, QR=6 cm, PR=7.5 cm and triangle PQR is similar to triangle XYZ. If XY=18 cm, find the value of YZ.

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.

The difference between the interior and the exterior angles of a regular polygon is 150^o. Find the number of sides in the polygon.

If the ratio of the measurements of the three angles of a triangle is 2: 3: 4, then the measurement of its largest angle is.

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?