RD Chapter 14- Co-ordinate Geometry Ex-14.1 |
RD Chapter 14- Co-ordinate Geometry Ex-14.2 |
RD Chapter 14- Co-ordinate Geometry Ex-14.3 |
RD Chapter 14- Co-ordinate Geometry Ex-14.5 |

Find the centroid of the triangle whose vertices are :

(i) (1, 4), (-1, -1), (3, -2)

(ii) (-2, 3), (2, -1), (4, 0)

**Answer
1** :

**Answer
2** :

Centroid of a triangle is O(0, 0) ….(i)

Co-ordinates of two vertices of a ∆ABC are A (1, 2) and B (3, 5)

Let the third vertex be (x, y)

**Answer
3** :

Let two vertices of a ∆ABC be A (-3, 1) and B (0, -2) and third vertex C be (x, y)

Centroid of the ∆ABC is O (0, 0)

**Answer
4** :

A (3, 2) and B (-2, 1) are the two vertices of ∆ABC whose centroid is G (5/3 , −1/3)

Let third vertex C be (x, y)

**Answer
5** :
In ∆ABC, D, E and F are the mid-points of the sidesBC, CA and AB respectively.

The co-ordinates of D are (-2, 3), of E are (4,-3) and of F are (4, 5)

Let the co-ordinates of A, B and C be (x_{1}, y_{1}),(x_{2}, y_{2}), (x_{3}, y_{3})respectively

**Answer
6** :

In ∆ABC,

D and E are the mid points of the sides AB and AC respectively

**Answer
7** :

Let A (x1, y1), B (x2, y2), C (x3, y3) and D (x4, y4) be the vertices of quadrilateral ABCD

E and F are the mid points of side BC and AD respectively and EF is joined G and H are the mid points of diagonal AC and BD.

GH are joined