Table of Contents

## Explain in Detail :Plane Surface

A plane surface is a surface that extends infinitely in all directions. A plane is a two-dimensional surface that has no thickness.

## Plane Curve

A plane curve is a curve that lies in a plane.

## Polygons

A polygon is a closed figure that is made up of straight lines. A polygon has at least three sides.

A polygon has at least three sides. A polygon has at least four sides. A polygon has at least five sides. A polygon has at least six sides. A polygon has at least seven sides. A polygon has at least eight sides. A polygon has at least nine sides. A polygon has at least ten sides.

## Understanding Quadrilaterals Class 8 Exercise 3.2

Question 1:

Name the quadrilaterals.

A. A square

B. A rectangle

C. A parallelogram

D. A trapezium

E. A kite

A. Square, rectangle, parallelogram, trapezium, kite

Question 2:

State the properties of a square.

A square has four equal sides and four right angles.

## Concave and Convex Polygons

A concave polygon is a polygon in which at least one interior angle is greater than 180 degrees. A convex polygon is a polygon in which no interior angle is greater than 180 degrees.