English

The points A(– 2, 1), B(0, 5), C(– 1, 2) are collinear.

Advertisements
Advertisements

Question

The points A(– 2, 1), B(0, 5), C(– 1, 2) are collinear.

Options

  • True

  • False

MCQ
True or False
Advertisements

Solution

This statement is False.

Explanation:

Given points are A(– 2, 1), B(0, 5), C(– 1, 2)

Area of ΔABC = `1/2|(-2, 1, 1),(0, 5, 1),(-1, 2, 1)|`

= `1/2 -2|(5, 1),(2, 1)| -1|(0, 1),(-1, 1)| + 1|(0, 5),(-1, 2)|`

= `1/2 |-2(5 - 2) - 1(0 + 1) + 1(0 + 5)|`

= `1/2 |-2 xx 3 - 1 xx 1 + 1 xx 5|`

= `1/2|-6 - 1 + 5|`

= `1/2|-2|`

= 1 sq.unit

So, the given points are not collinear.

shaalaa.com
  Is there an error in this question or solution?
Chapter 10: Straight Lines - Exercise [Page 183]

APPEARS IN

NCERT Exemplar Mathematics [English] Class 11
Chapter 10 Straight Lines
Exercise | Q 49 | Page 183

Video TutorialsVIEW ALL [1]

RELATED QUESTIONS

Find a point on the x-axis, which is equidistant from the points (7, 6) and (3, 4).


Find the angle between the x-axis and the line joining the points (3, –1) and (4, –2).


The slope of a line is double of the slope of another line. If tangent of the angle between them is `1/3`, find the slopes of the lines.


A line passes through (x1, y1) and (h, k). If slope of the line is m, show that k – y1 = m (h – x1).


If three point (h, 0), (a, b) and (0, k) lie on a line, show that `q/h + b/k = 1`


Find the values of k for which the line (k–3) x – (4 – k2) y + k2 –7k + 6 = 0 is 

  1. Parallel to the x-axis,
  2. Parallel to the y-axis,
  3. Passing through the origin.

Find the slope of the lines which make the following angle with the positive direction of x-axis:

\[\frac{2\pi}{3}\]


Using the method of slope, show that the following points are collinear A (16, − 18), B (3, −6), C (−10, 6) .


What is the value of y so that the line through (3, y)  and (2, 7) is parallel to the line through (−1, 4) and (0, 6)?


Without using Pythagoras theorem, show that the points A (0, 4), B (1, 2) and C (3, 3) are the vertices of a right angled triangle.


The slope of a line is double of the slope of another line. If tangents of the angle between them is \[\frac{1}{3}\],find the slopes of the other line.


Without using the distance formula, show that points (−2, −1), (4, 0), (3, 3) and (−3, 2) are the vertices of a parallelogram.


Find the equation of a straight line with slope 2 and y-intercept 3 .


Find the equations of the straight lines which cut off an intercept 5 from the y-axis and are equally inclined to the axes.


Find the angles between the following pair of straight lines:

3x − y + 5 = 0 and x − 3y + 1 = 0


Find the angles between the following pair of straight lines:

3x + 4y − 7 = 0 and 4x − 3y + 5 = 0


Find the angles between the following pair of straight lines:

(m2 − mn) y = (mn + n2) x + n3 and (mn + m2) y = (mn − n2) x + m3.


If θ is the angle which the straight line joining the points (x1, y1) and (x2, y2) subtends at the origin, prove that  \[\tan \theta = \frac{x_2 y_1 - x_1 y_2}{x_1 x_2 + y_1 y_2}\text { and } \cos \theta = \frac{x_1 x_2 + y_1 y_2}{\sqrt{{x_1}^2 + {y_1}^2}\sqrt{{x_2}^2 + {y_2}^2}}\].


Find the tangent of the angle between the lines which have intercepts 3, 4 and 1, 8 on the axes respectively.


Write the coordinates of the image of the point (3, 8) in the line x + 3y − 7 = 0.


The medians AD and BE of a triangle with vertices A (0, b), B (0, 0) and C (a, 0) are perpendicular to each other, if


If the line joining two points A(2, 0) and B(3, 1) is rotated about A in anticlock wise direction through an angle of 15°. Find the equation of the line in new position.


Find the equation to the straight line passing through the point of intersection of the lines 5x – 6y – 1 = 0 and 3x + 2y + 5 = 0 and perpendicular to the line 3x – 5y + 11 = 0.


The intercept cut off by a line from y-axis is twice than that from x-axis, and the line passes through the point (1, 2). The equation of the line is ______.


The reflection of the point (4, – 13) about the line 5x + y + 6 = 0 is ______.


If p is the length of perpendicular from the origin on the line `x/a + y/b` = 1 and a2, p2, b2 are in A.P, then show that a4 + b4 = 0.


The equation of the straight line passing through the point (3, 2) and perpendicular to the line y = x is ______.


Equation of the line passing through (1, 2) and parallel to the line y = 3x – 1 is ______.


One vertex of the equilateral triangle with centroid at the origin and one side as x + y – 2 = 0 is ______.


The vertex of an equilateral triangle is (2, 3) and the equation of the opposite side is x + y = 2. Then the other two sides are y – 3 = `(2 +- sqrt(3)) (x - 2)`.


Column C1 Column C2
(a) The coordinates of the points
P and Q on the line x + 5y = 13 which
are at a distance of 2 units from the
line 12x – 5y + 26 = 0 are
(i) (3, 1), (–7, 11)
(b) The coordinates of the point on
the line x + y = 4, which are at a  unit
distance from the line 4x + 3y – 10 = 0 are
(ii) `(- 1/3, 11/3), (4/3, 7/3)`
(c) The coordinates of the point on the line
joining A (–2, 5) and B (3, 1) such that
AP = PQ = QB are
(iii) `(1, 12/5), (-3, 16/5)`

The equation of the line through the intersection of the lines 2x – 3y = 0 and 4x – 5y = 2 and

Column C1 Column C2
(a) Through the point (2, 1) is (i) 2x – y = 4
(b) Perpendicular to the line (ii) x + y – 5
= 0 x + 2y + 1 = 0 is
(ii) x + y – 5 = 0
(c) Parallel to the line (iii) x – y –1 = 0
3x – 4y + 5 = 0 is
(iii) x – y –1 = 0
(d) Equally inclined to the axes is (iv) 3x – 4y – 1 = 0

The line which passes through the origin and intersect the two lines `(x - 1)/2 = (y + 3)/4 = (z - 5)/3, (x - 4)/2 = (y + 3)/3 = (z - 14)/4`, is ______.


The three straight lines ax + by = c, bx + cy = a and cx + ay = b are collinear, if ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×