Page 87 - Viva

• A corner in a plane figure is the point where two straight lines meet.

Side
Corner A B Corner

• A side is a straight line joining two corner points
lying adjacent (side by side) to each other. Side Side

Corner D C Corner
Side
P Q
Diagonal Diagonal • A diagonal is the line joining the opposite and

non-adjacent corners of a straight-sided shape.

S R

We already know about some basic 2D shapes. Let’s quickly revise them.
A B

Square
Corner Diagonal
It has four equal sides. It has 4 corners and 2 diagonals.

D Side C
AB = BC = CD = DA
A B
Corner AB = DC Rectangle
Side Diagonal BC = AD It has four sides (2 short and 2 long).
(Short)
Its opposite sides are equal. It has 4 corners
D Side C and 2 diagonals.
(Long)

A
Corner
Triangle
It has three sides and three corners. It has no diagonals.

B C
Side

Circle
It has no sides, corners and diagonals.

Oval

It has no sides, corners and diagonals. It is like a flattened circle.

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