Forum

Circles

Prove that the tangent drawn at the mid-point of an arc of a circle is parallel to the chord joining the end points of the arc.

08/11/2024

Mathematics

10th

Circles

AB  is  a  diameter  and AC  is  a  chord  of  a  circle  with  centre  O  such  that ∠BAC = 30°. The tangent at C intersects extended AB at a point D. Prove that BC = BD.

08/11/2024

Mathematics

10th

Circles

In Figure, tangents PQ and PR are drawn to a circle such that ∠RPQ = 30°. A chord RS is drawn parallel to the tangent PQ. Find the ∠RQS.

[Hint: Draw a line through Q and perpendicular to QP.]

08/11/2024

Mathematics

10th

Circles

In a right triangle ABC in which  ∠B = 90°, a circle is drawn with AB as diameter intersecting the hypotenuse AC and P. Prove that the tangent to the circle at P bisects BC.

08/11/2024

Mathematics

10th

Circles

Two  circles  with  centres  O  and  O’  of  radii  3  cm  and  4  cm,  respectively intersect at two points P and Q such that OP and O’P are tangents to the two circles. Find the length of the common chord PQ.

08/11/2024

Mathematics

10th

Circles

If AB is a chord of a circle with centre O, AOC is a diameter and AT is the tangent at A as shown in Figure. Prove that ∠BAT = ∠ACB.

 

08/11/2024

Mathematics

10th

Circles

From an external point P, two tangents, PA and PB are drawn to a circle with centre O. At one point E on the circle tangent is drawn which intersects PA and PB at C and D, respectively. If PA = 10 cm, find the the perimeter of the triangle PCD.

08/11/2024

Mathematics

10th

Circles

Let s denote the semi-perimeter of a triangle ABC in which BC = a, CA = b, AB = c. If a circle touches the sides BC, CA, AB at D, E, F, respectively, prove that BD = s – b.

08/11/2024

Mathematics

10th

Circles

If  a  hexagon  ABCDEF  circumscribe  a  circle,  prove  that AB + CD + EF = BC + DE + FA.

08/11/2024

Mathematics

10th

Circles

If a circle touches the side BC of a triangle ABC at P and extended sides AB and AC at Q and R, respectively, prove that AQ = 1/2 (BC + CA + AB) .

08/11/2024

Mathematics

10th