# Understanding Quadrilaterals

## Exercise 3.1

1). Given here are some figures.

Classify each of them on the basis of the following.

(a) Simple curve (b) Simple closed curve

(c) Polygon (d) Convex polygon

(e) Concave polygon

Answer:

(a) Simple curve

Ans: Fig 1, 2, 5, 6, 7

(b) Simple closed curve

Ans: Fig 1, 2, 5, 6, 7

(c) Polygon

Ans: Fig 1 and 2

(d) Convex polygon

Ans: Fig 2.

(e) Concave polygon

Ans: Fig 1

2). What is a regular polygon?

Ans: A regular polygon is both ‘equiangular’ and ‘equilateral’.

3). State the name of a regular polygon of

(i) 3 sides (ii) 4 sides (iii) 6 sides

Answer:

(i) 3 sides

Ans: Equilateral triangle

(ii) 4 sides

Ans: Square

(iii) 6 sides

Ans: Regular Hexagon