**Chapter 4 Basic Geometrical Ideas Ex 4.2**

Question 1.

Classify the following curves as (i) open or (ii) closed.

Solution:

(a) Open curve

(b) Closed curve

(c) Open curve

(d) Closed curve

Question 2.

Draw rough diagrams to illustrate the following:

(a) Open curve

(b) Closed curve

Solution:

Question 3.

Draw any polygon and shade

Solution:

ABCD is the required polygon whose interior region is shaded.

Question 4.

Consider the given figure and answer the questions.

(a) Is it a curve?

(b) Is it closed?

Solution:

(a) Yes, it is a curve.

(b) Yes, it is closed curve.

Question 5.

Illustrate, if possible, each one of the following with a rough diagram:

(a) A closed curve that is not a polygon.

(b) An open curve made up entirely of line segments.

(c) A polygon with two sides.

Solution:

(a) Required closed curve is a circle.

(b) ABCD is an open curve made up of the line segments AB¯¯¯¯¯¯¯¯, BC¯¯¯¯¯¯¯¯ and CD¯¯¯¯¯¯¯¯ .

(c) A polygon with two sides is not possible.

IMG