Plane geometry

Circles

Types of exercises: inscribed and central angles, circle circumscribed on a right triangle, tangent to a circle, chord of a circle, tangent segments, incircle and circumcircle.

Exercises are drawn at random from a large bank - every click gives a different set.

Solved: 0 of 10

1

Find the distance of the chord from the centre

A chord of a circle of radius 12 cm is 22 cm long. How far from the centre of the circle is the chord?

2

Compute the radius of the circumscribed circle

A right triangle has legs 30 cm and 72 cm. What is the radius of the circle circumscribed on it?

3

Find the perimeter of the triangle

The incircle of triangle ABC touches the sides AB, BC and CA at the points K, L and M respectively. |AK| = 8 cm, |BL| = 7 cm, |CM| = 14 cm. What is the perimeter of triangle ABC?

4

Find the radius of the incircle

A square has a side of 18 cm. What is the radius of the circle inscribed in it?

5

Compute the length

A circle has radius 84 cm. A tangent from some point touches it, and the segment from that point to the point of contact is 13 cm. How far is that point from the centre?

6

Give the measure of the angle

A central angle of a circle measures 68 degrees. What is the inscribed angle on the same arc?

7

Find the radius of the circle

A chord of a circle is 60 cm long and is 40 cm from the centre of the circle. What is the radius of the circle?

8

Compute the length

The circle circumscribed on a right triangle has a radius of 7.5 cm, and one leg of the triangle is 12 cm. How long is the other leg?

9

Find the radius of the circle

Two tangents are drawn from a point P to a circle with centre O; they touch the circle at A and B, |∠APB| = 60° and |PA| = 4√3 cm. What is the radius of the circle?

10

Find the length of the side

The incircle of an equilateral triangle has a radius of 8√3 cm. How long is a side of the triangle?

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Circles - exercises with solutions (Plane geometry) | PhiBoard