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5. State whether the following statements are ‘True’ or ‘False’.

(a) All squares are rectangles.

(b) All rectangles are squares.

(c) A polygon has two sides.

(d) There are four vertices in a square.

(e) All quadrilaterals are rectangles.

circLes

Look at these objects and observe their shapes.

The shape of each object represents a circle. You can see

many objects around you which have the shape of a circle.

A circle is a simple closed curve, all points on which are at an circle
equal distance from a fixed point inside it. The fixed point is called O centre

the centre of the circle.

Parts of a circle

Think Tank
Take a sheet of paper and trace a circle on it using Why is a circle not considered

a bangle. Cut along the traced line and fold the a polygon, even though it is a
paper circle twice to make creases as shown below. closed figure?

Open and observe it. The point where the two creases meet is called the centre of

the circle and the crease passing through the centre is called the diameter of the
circle.

Creases (Diameters)
1st fold 2nd fold Unfold
Centre

The distance from the centre of Centre of
circle (O)
the circle to any point on the circle Diameter (AB)
is called the radius of the circle. O Be Aware
A B The plural of
A half circle is called a semicircle. Radius (OR) radius is radii.

The distance around the circle All radii of a
circle are equal
is called the circumference. R Circumference in length.

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