Page 87 - Start Up Mathematics_6

(d) ED and AC are the two chords.
(e) O and P are two points in the interior.
(f) Q is a point in the exterior.
(g) Regions ERAOE and ABCA are the two sectors.
(h) Region EXD is the minor segment.

Example 17: Answer the following questions:
(a) Is every diameter of a circle also a chord? Is the converse true?
(b) Is a circle a simple closed curve?
Solution: (a) Yes, every diameter of a circle is a chord, but the converse is not true.
(b) Yes, a circle is a simple closed curve.

EXERCISE 4.2

1. State true or false:
(a) A radius of a circle is also a chord.
(b) Minor arc is less than a semicircle.

(c) A segment of a circle can never coincide with a sector.
(d) Minor arc is greater than major arc.

(e) Diameter is the longest chord of the circle.
2. Find the length of the longest chord of a circle having radius 7 cm.
3. Draw a circle and mark two points:
(a) in its exterior (b) in its interior (c) on the circle

4. Two points A and B are given. How many circles can be drawn
(a) passing through one point say A?

(b) passing through both the points A and B?
(c) passing through A with B as the centre?
5. Draw any circle and show:
(a) its centre (b) a radius (c) a diameter

(d) a sector (e) a segment (f) an arc C
6. Draw both the diagonals of the given quadrilateral. Mention D B
which diagonal lies in the interior of the quadrilateral and which
lies in its exterior.
A

At a Glance

1. A point is a mark of position. It has no length, breadth or thickness.
2. A line is a collection of points along an endless straight path.

3. The part of a line from one fixed point to the other is called a line segment. It has definite length.

4. If two lines meet each other at one point, then they are called intersecting lines.
5. Two lines are parallel, if they have no common point.
6. Three or more points are collinear if they lie on a line.

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