Advertisements
Advertisements
Question
In the following example find the co-ordinate of point A which divides segment PQ in the ratio a : b.
P(2, 6), Q(–4, 1), a : b = 1 : 2
Solution
Let the coordinates of point A be (x, y).
P(2, 6), Q(–4, 1), a : b = 1 : 2
Using section formula
\[x = \frac{1 \times \left( - 4 \right) + 2 \times 2}{1 + 2} = \frac{- 4 + 4}{3} = 0\]
\[y = \frac{1 \times 1 + 2 \times 6}{1 + 2} = \frac{1 + 12}{3} = \frac{13}{3}\]
\[\left( x, y \right) = \left( 0, \frac{13}{3} \right)\]
APPEARS IN
RELATED QUESTIONS
Points A(–5, x), B(y, 7) and C(1, –3) are collinear (i.e. lie on the same straight line) such that AB = BC. Calculate the values of x and y.
Prove that the points A(–5, 4); B(–1, –2) and C(5, 2) are the vertices of an isosceles right-angled triangle. Find the co-ordinates of D so that ABCD is a square.
Write the co-ordinates of the point of intersection of graphs of
equations x = 2 and y = -3.
Point P is the midpoint of seg AB. If co-ordinates of A and B are (-4, 2) and (6, 2) respectively then find the co-ordinates of point P.
(A) (-1,2) (B) (1,2) (C) (1,-2) (D) (-1,-2)
Find the midpoint of the line segment joining the following pair of point :
(4,7) and (10,15)
Find the midpoint of the line segment joining the following pair of point :
(3a-2b, Sa+7b) and (a+4b, a-3b)
The mid-point of the line segment joining A (- 2 , 0) and B (x , y) is P (6 , 3). Find the coordinates of B.
A , B and C are collinear points such that AB = `1/2` AC . If the coordinates of A, B and C are (-4 , -4) , (-2 , b) anf (a , 2),Find the values of a and b.
AB is a diameter of a circle with centre 0. If the ooordinates of A and 0 are ( 1, 4) and (3, 6 ). Find the ooordinates of B and the length of the diameter.
The three vertices of a parallelogram taken in order are (-1, 0), (3, 1) and (2, 2) respectively. Find the coordinates of the fourth vertex.
Find the mid-point of the line segment joining the points
(−2, 3) and (−6, −5)
Find the mid-point of the line segment joining the points
(8, −2) and (−8, 0)
Find the mid-point of the line segment joining the points
`(1/2, (-3)/7)` and `(3/2, (-11)/7)`
The ratio in which the x-axis divides the line segment joining the points A (a1, b1) and B (a2, b2) is
The coordinates of diameter AB of a circle are A(2, 7) and B(4, 5), then find the coordinates of the centre
Find coordinates of midpoint of the segment joining points (0, 2) and (12, 14)
From the figure given alongside, find the length of the median AD of triangle ABC. Complete the activity.
Solution:
Here A(–1, 1), B(5, – 3), C(3, 5) and suppose D(x, y) are coordinates of point D.
Using midpoint formula,
x = `(5 + 3)/2`
∴ x = `square`
y = `(-3 + 5)/2`
∴ y = `square`
Using distance formula,
∴ AD = `sqrt((4 - square)^2 + (1 - 1)^2`
∴ AD = `sqrt((square)^2 + (0)^2`
∴ AD = `sqrt(square)`
∴ The length of median AD = `square`
If A(5, 4), B(–3, –2) and C(1, –8) are the vertices of a ∆ABC. Segment AD is median. Find the length of seg AD:
Point M (2, b) is the mid-point of the line segment joining points P (a, 7) and Q (6, 5). Find the values of ‘a’ and ‘b’.
Find the co-ordinates of centroid of a triangle if points D(–7, 6), E(8, 5) and F(2, –2) are the mid-points of the sides of that triangle.