**Basic Geometrical Ideas**

## Exercise 4.1

## Ex 4.1 Question 1.

**1. Use the figure to name:**

**(a) Five points**

**(b) A line**

**(c) Four rays**

**(d) Five line segments**

(a) Five points = B ,C ,D ,E and O

(b) A line

(c) Four rays

,

,

and

.

(d) Five line segments

,

,

,

and

## Ex 4.1 Question 2.

**Name the line given in all possible (twelve) ways, choosing only two letters at a time from the four given.**

**Solutions:**

The lines are

,

,

,

,

,

,

,

,

,

,

,

## Ex 4.1 Question 3.

** Use the figure to name:**

**(a) Line containing point E.**

**(b) Line passing through A.**

**(c) Line on which O lies**

**(d) Two pairs of intersecting lines.**

**Solutions:**

(a) Line containing point E

(b) Line passing through A

(c) Line on which O lies

(d) Two pairs of intersecting lines

,

and

,

## Ex 4.1 Question 4.

**How many lines can pass through (a) one given point? (b) two given points?**

**Solutions:**

(a) An infinite number of lines can pass through one given point.

(b) Only one line can pass through two given points.

## Ex 4.1 Question 5.

**Draw a rough figure and label suitably in each of the following cases:**

**(a) Point P lies on .**

**(b)** ** and intersect at M.**

**(c) Line l contains E and F but not D.**

**(d) and meet at O.**

**Solutions:**

## Ex 4.1 Question 6.

**6. Consider the following figure of line . Say whether following statements are true or false in context of the given figure.**

**(a) Q, M, O, N, P are points on the line .**

**(b) M, O, N are points on a line segment .**

**(c) M and N are end points of line segment.**

**(d) O and N are end points of line segment .**

**(e) M is one of the end points of line segment .**

**(f) M is point on ray .**

**(g) Ray **** is different from ray .**

**(h) Ray is same as ray .**

**(i) Ray is not opposite to ray .**

**(j) O is not an initial point of **

**(k) N is the initial point of and .**

**Solutions:**

(a) True

(b) True

(c) True

(d) False

(e) False

(f) False

(g) True

(h) False

(i) False

(j) False

(k) True