2nd Class Mathematics Geometrical Figures

Geometrical Figures

Category : 2nd Class

Geometrical Figures

Line

Let's see the lines given below:

• Example:

Give the name of all slant lines from the figure given below.

(a) AD and BC                             (B) AB and BC

(c) AB and AD                            (D) All the above

(e) None of these

• Example:

Which one of the following is correct about the line?

(a) A straight line is measured by ruler.

(b) A straight line cannot be measured by ruler.

(c) A straight line is measured in grams.

(d) All the above

(e) None of these

Note: We use ruler to measure a straight line.

Angle

An angle is formed at the meeting point of two lines or an angle is formed when two lines meet. The point where two lines meet is called vertex. See the figures given below:

• Example:

Which one of the following is correct about the angle?

(a) Both sides of an angle must be equal in length

(b) Both sides of an angle may be unequal in length

(c) Two lines cannot form an angle

(d) Three lines are required for formation of an angle

(e) None of these

• Example:

Which one of the following is representing an angle?

Note: Both the sides of an angle may be unequal in length.

Square

A square has four equal sides and four equal angles.

In this picture side AB = BD = CD = AC

And  $\angle A=\angle B=\angle C=\angle D=90{}^\circ$

• Example:

If the sum of three angles of a square is$270{}^\circ$, then the measurement of its fourth angle will be?

(a) $70{}^\circ$                                  (b) $80{}^\circ$

(c) $90{}^\circ$                                               (d) All the above

(e) None of these

Explanation: Each angle of the square is$90{}^\circ$.

Properties

1. 4 sides (edges)
2. 4 vertices (corner)

• Example:

A plane figure has four sides and four vertices. The name of the plane figure is:

(c) Pentagon                               (d) All the above

(e) None of these

Rectangle

Properties

In a rectangle:

1. Opposite sides are equal.
2. Opposite sides are parallel.
3. All angles are equal.

See the figure given below:

Here,

AB = CD

And AC = BD

$\angle A=\angle B=\angle C=\angle D=90{}^\circ$

Similarly

• Example:

Which one of the following is correct about a rectangle, if a pair of opposite sides is PQ and RS, another pair of opposite sides is PS and QR?

(a) $PQ\ne RS\,\,and\,\,PS=QR$

(b) $PQ=RS\,\,and\,\,PS=QR$

(c) $PQ=PS=RS=QR$

(d) All of these

(e) None of these

Explanation: Opposite sides of a are rectangle are equal.

Note: A rectangle is a quadrilateral.

Rhombus

Properties

In a rhombus:

1. All sides of a Rhombus are equal.
2. Diagonals of a rhombus are perpendicular to each other. That is they intersect at

See the figure given below:

Here, the sides

AB = BC = CD = AD

• Example:

Which one of the following differentiates the rhombus and square?

(a) Rhombus has all equal sides

(b) Rhombus has all unequal sides

(c) Each angle of a rhombus may not be a right angle

(d) All the above

(e) None of these

Parallelogram

Properties

In a parallelogram:

1. Opposite sides are equal
2. Opposite angles are equal.

See the parallelogram given below

Here, the sides AB = CD & AB | | CD

And the opposite angles, $\angle A=\angle C\,\,\And \,\,\angle B=\angle D$