Advertisements
Advertisements
प्रश्न
Use distance formula to show that the points A(-1, 2), B(2, 5) and C(-5, -2) are collinear.
उत्तर
If using distance formula we have to prove that A, B and C are collinear, then we have to show:
BC = AC + AB
Hence AB = `sqrt((5 - 2)^2 + (2 + 1)^2) = sqrt(9 + 9)`
= `sqrt(18) = 3sqrt(2)"units"`.
BC = `sqrt((-2 - 5)^2 + (- 5 - 2)^2)`
= `sqrt(49 + 49) = sqrt(98) = 7sqrt(2)"units"`.
and AC = `sqrt((-2 - 2)^2 + (-5 + 1)^2)`
= `sqrt(16 + 16) = sqrt(32) = 4sqrt(2)"units"`.
as `7sqrt(2) = 4sqrt(2) + 3sqrt(2)`
⇒ BC = AB + AC
⇒ Points A,B and C are collinear.
Hence proved.
APPEARS IN
संबंधित प्रश्न
If the point A(0, 2) is equidistant from the points B(3, p) and C(p, 5), find p. Also, find the length of AB.
Show that the points (a, a), (–a, –a) and (– √3 a, √3 a) are the vertices of an equilateral triangle. Also find its area.
In a classroom, 4 friends are seated at the points A, B, C and D as shown in the following figure. Champa and Chameli walk into the class and after observing for a few minutes, Champa asks Chameli, “Don’t you think ABCD is a square?” Chameli disagrees.
Using distance formula, find which of them is correct.
If a≠b≠0, prove that the points (a, a2), (b, b2) (0, 0) will not be collinear.
ABC is a triangle and G(4, 3) is the centroid of the triangle. If A = (1, 3), B = (4, b) and C = (a, 1), find ‘a’ and ‘b’. Find the length of side BC.
PQR is an isosceles triangle . If two of its vertices are P (2 , 0) and Q (2 , 5) , find the coordinates of R if the length of each of the two equal sides is 3.
In what ratio does the point P(−4, y) divides the line segment joining the points A(−6, 10) and B(3, −8)? Hence find the value of y.
Points A (-3, -2), B (-6, a), C (-3, -4) and D (0, -1) are the vertices of quadrilateral ABCD; find a if 'a' is negative and AB = CD.
Calculate the distance between A (7, 3) and B on the x-axis whose abscissa is 11.
KM is a straight line of 13 units If K has the coordinate (2, 5) and M has the coordinates (x, – 7) find the possible value of x.