English

Show that the points A (5, 6), B (1, 5), C (2, 1) and D (6, 2) are the vertices of a square ABCD.

Advertisements
Advertisements

Question

Show that the points A (5, 6), B (1, 5), C (2, 1) and D (6, 2) are the vertices of a square ABCD.

Sum
Advertisements

Solution

We use the distance formula = `sqrt((x_2 - x_1)^2 + (y_2 - y_1)^2)` to find the length of each side.

AB = `sqrt((1 - 5)^2 + (5 - 6)^2)`

= `sqrt((-4)^2 + (-1)^2)`

= `sqrt(16 +1)`

= `sqrt(17)`

BC = `sqrt((2 - 1)^2 + (1 - 5)^2)`

= `sqrt((1)^2 + (-4)^2)`

= `sqrt(1+16)`

= `sqrt(17)`

CD = `sqrt((6 - 2)^2 + (2 - 1)^2)`

= `sqrt((4)^2 + (1)^2)`

= `sqrt(16 + 1)`

= `sqrt(17)`

DA = `sqrt((5 - 6)^2 + (6 - 2)^2)`

= `sqrt((-1)^2 + (4)^2)`

= `sqrt(1+16)`

 = `sqrt(17)`

To prove it is a square, the diagonals must also be equal in length.

AC = `sqrt((2 - 5)^2 + (1 - 6)^2)`

= `sqrt((-3)^2 + (-5)^2)`

= `sqrt(9+25)`

= `sqrt(34)`

BD = `sqrt((6 - 1)^2 + (2 - 5)^2)`

= `sqrt((5)^2 + (-3)^2)`

= `sqrt(25 + 9)` 

= `sqrt(34)`

The diagonals have the same length, `sqrt(34)` units.

Since, AB = BC = CD = DA and AC = BD,

A, B, C and D are the vertices of a square.

shaalaa.com
  Is there an error in this question or solution?
Chapter 28: Distance Formula - Exercise 28 [Page 335]

APPEARS IN

Selina Concise Mathematics [English] Class 9 ICSE
Chapter 28 Distance Formula
Exercise 28 | Q 14 | Page 335

RELATED QUESTIONS

Find the point on the x-axis which is equidistant from (2, -5) and (-2, 9).


A(–8, 0), B(0, 16) and C(0, 0) are the vertices of a triangle ABC. Point P lies on AB and Q lies on AC such that AP : PB = 3 : 5 and AQ : QC = 3 : 5. Show that : PQ = `3/8` BC.


Find the distance between the points

A(-6,-4) and B(9,-12)


Determine whether the points are collinear.

A(1, −3), B(2, −5), C(−4, 7)


Prove that the points (1 ,1),(-4 , 4) and (4 , 6) are the certices of an isosceles triangle.


ABC is an equilateral triangle . If the coordinates of A and B are (1 , 1) and (- 1 , -1) , find the coordinates of C.


Prove that the points A (1, -3), B (-3, 0) and C (4, 1) are the vertices of an isosceles right-angled triangle. Find the area of the triangle.


The length of line PQ is 10 units and the co-ordinates of P are (2, -3); calculate the co-ordinates of point Q, if its abscissa is 10.


The distance between the points A(0, 6) and B(0, -2) is ______.


Tharunya was thrilled to know that the football tournament is fixed with a monthly timeframe from 20th July to 20th August 2023 and for the first time in the FIFA Women’s World Cup’s history, two nations host in 10 venues. Her father felt that the game can be better understood if the position of players is represented as points on a coordinate plane.

  1. At an instance, the midfielders and forward formed a parallelogram. Find the position of the central midfielder (D) if the position of other players who formed the parallelogram are :- A(1, 2), B(4, 3) and C(6, 6)
  2. Check if the Goal keeper G(–3, 5), Sweeper H(3, 1) and Wing-back K(0, 3) fall on a same straight line.
    [or]
    Check if the Full-back J(5, –3) and centre-back I(–4, 6) are equidistant from forward C(0, 1) and if C is the mid-point of IJ.
  3. If Defensive midfielder A(1, 4), Attacking midfielder B(2, –3) and Striker E(a, b) lie on the same straight line and B is equidistant from A and E, find the position of E.

Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×