On increasing the radius of circle by 1 cm, its area is increased by 44 cm² .The original radius of the circle is -

In a triangle, if orthocentre, circumcentre, incentre and centroid coincide, then the triangle must be

PK is the median and M is a centroid of triangle PQR. If PK is 15 cm, then find length of PM?

AC is a chord of circle whose centre is at O. If B is any point on the arc AC and ∠OCA=20⁰ , then the magnitude of ∠ABC is

The two vowels touch each other internally. Their radii are 2 cm and 3 cm. What will be the length of the largest chord of the bigger circle outside the inner circle?

The side of a trapezium pyramid with a square base is 24 cm. and its height is 5 cm. What will be the area of its oblique surface in cm²?

The diameter of the circle with center O is AB. PQ is the chord that does not intersect AB. Join AP and BQ. If ∠BAP = ∠ABQ,  then what will be ABQP?

In ΔABC, D and E are points on the sides AB and AC, respectively, such that DE || BC. If AD = 5 cm, DB = 9 cm, AE = 4 cm and BC = 15.4 cm, then the sum of the lengths of DE and EC (in cm) is: