English

Find the combined equation of bisectors of angles between the lines represented by 5x2 + 6xy - y2 = 0.

Advertisements
Advertisements

Question

Find the combined equation of bisectors of angles between the lines represented by 5x2 + 6xy - y2 = 0.

Sum
Advertisements

Solution

Comparing the equation 5x2 + 6xy - y2 = 0 with ax2 + 2hxy + by2 = 0, we get,

a = 5, 2h = 6, b = -1

Let m1 and m2 be the slopes of the lines represented by 5x2 + 6xy - y2 = 0.

∴ m1 + m2 = `(-2"h")/"b" = (-6)/-1 = 6`  and m1m2 = `"a"/"b" = 5/-1 = - 5`    ...(1)

The separate equations of the lines are

y = m1x and y = m2x, where m1 ≠ m2

i.e. m1x - y = 0 and m2x - y = 0.

Let P(x, y) be any point on one of the bisector of the angles between the lines.

∴ the distance of P from the line m1x - y = 0 is equal to the distance of P from the line m2x - y = 0.

∴ `|("m"_1"x" - "y")/(sqrt("m"_1^2 + 1))| = |("m"_2"x" - "y")/(sqrt("m"_2^2 + 1))|`

Squaring both sides, we get,

`("m"_1"x" - "y")^2/("m"_1^2 + 1) = ("m"_2"x" - "y")/("m"_2^2 + 1)`

∴ `("m"_2^2 + 1)("m"_1"x" - "y")^2 = ("m"_1^2 + 1)("m"_2"x" - "y")`

∴ `("m"_2^2 + 1)("m"_1^2"x"^2 - 2"m"_1"xy" + "y"^2) = ("m"_1^2 + 1)("m"_2^2"x"^2 - 2"m"_2"xy" + "y"^2)`


∴ `"m"_1^2"m"_2^2"x"^2 - 2"m"_1"m"_2^2"y"^2"xy" + "m"_2^2"y"^2 + "m"_1^2"x"^2 - 2"m"_1"xy" + "y"^2 = "m"_1^2"m"_2^2"x"^2 - 2"m"_1^2"m"_2"xy" + "m"_1^2"y"^2 + "m"_2^2"x"^2 - 2"m"_2"xy" + "y"^2`

∴ `("m"_1^2 - "m"_2^2)"x"^2 + 2"m"_1"m"_2("m"_1 -"m"_2)"xy" - 2("m"_1 - "m"_2)"xy" - ("m"_1^2 - "m"_2^2)"y"^2 = 0`

Dividing throughout by `"m"_1- "m"_2` (≠ 0), we get, 

`("m"_1 + "m"_2)"x"^2 + 2"m"_1"m"_2"xy" - 2"xy" - ("m"_1 + "m"_2)"y"^2 = 0`

∴ 6x2 - 10xy - 2xy - 6y2 = 0    ...[By (1)] 

∴ 6x2 - 12xy - 6y2 = 0 

∴ x2 - 2xy - y2 = 0

This is the joint equation of the bisectors of the angles between the lines represented by 5x2 + 6xy - y2 = 0.

shaalaa.com
  Is there an error in this question or solution?
Chapter 4: Pair of Straight Lines - Miscellaneous Exercise 4 [Page 132]

APPEARS IN

Balbharati Mathematics and Statistics 1 (Arts and Science) [English] Standard 12 Maharashtra State Board
Chapter 4 Pair of Straight Lines
Miscellaneous Exercise 4 | Q 10 | Page 132

RELATED QUESTIONS

Find the combined equation of the following pair of lines:

2x + y = 0 and 3x − y = 0


Find the combined equation of the following pair of line:

x + 2y - 1 = 0 and x - 3y + 2 = 0


Find the combined equation of the following pair of lines:

Passing through (2, 3) and perpendicular to the lines 3x + 2y – 1 = 0 and x – 3y + 2 = 0.


Find the separate equation of the line represented by the following equation:

x2 + 2xy tan α - y2 = 0


Find the combined equation of the pair of a line passing through the origin and perpendicular to the line represented by the following equation:

xy + y2 = 0 


Find the combined equation of the pair of a line passing through the origin and perpendicular to the line represented by the following equation:

3x2 − 4xy = 0 


If the slope of one of the two lines given by `"x"^2/"a" + "2xy"/"h" + "y"^2/"b" = 0` is twice that of the other, then ab : h2 = ______.


Choose correct alternatives:

If the equation 3x2 – 8xy + qy2 + 2x + 14y + p = 1 represents a pair of perpendicular lines, then the values of p and q are respectively ______.


Choose correct alternatives:

If h2 = ab, then slopes of lines ax2 + 2hxy + by2 = 0 are in the ratio


Choose correct alternatives:

If slope of one of the lines ax2 + 2hxy + by2 = 0 is 5 times the slope of the other, then 5h2 = ______


Find the joint equation of the line:

x - y = 0 and x + y = 0


Find the joint equation of the line passing through the origin and having inclinations 60° and 120°.


Find the joint equation of the line passing through (1, 2) and parallel to the coordinate axes


Find the joint equation of the line passing through (3, 2) and parallel to the lines x = 2 and y  = 3.


Find the joint equation of the line which are at a distance of 9 units from the Y-axis.


Show that the following equations represents a pair of line:

x2 + 2xy - y2 = 0


Show that the following equations represents a pair of line:

4x2 + 4xy + y2 = 0


Show that the following equations represent a pair of line:

x2 - y2 = 0


Show that the following equations represent a pair of line:

x2 + 7xy - 2y2 = 0


Find the joint equation of the pair of a line through the origin and perpendicular to the lines given by

x2 + 4xy - 5y2 = 0


Find the joint equation of the pair of a line through the origin and perpendicular to the lines given by

2x2 - 3xy - 9y2 = 0


Find the joint equation of the pair of a line through the origin and perpendicular to the lines given by

x2 + xy - y2 = 0


Find k, if the sum of the slopes of the lines given by 3x2 + kxy - y2 = 0 is zero.


Find k, if one of the lines given by 3x2 - kxy + 5y2 = 0 is perpendicular to the line 5x + 3y = 0.


Find the joint equation of the pair of lines through the origin and making an equilateral triangle with the line x = 3.


If the line 4x - 5y = 0 coincides with one of the lines given by ax2 + 2hxy + by2 = 0, then show that 25a + 40h + 16b = 0


Show that the following equation represents a pair of line. Find the acute angle between them:

2x2 + xy - y2 + x + 4y - 3 = 0


Show that the combined equation of the pair of lines passing through the origin and each making an angle α with the line x + y = 0 is x2 + 2(sec 2α)xy + y2 = 0


Find the condition that the equation ay2 + bxy + ex + dy = 0 may represent a pair of lines. 


If the lines given by ax2 + 2hxy + by2 = 0 form an equilateral triangle with the line lx + my = 1, show that (3a + b)(a + 3b) = 4h2.


If the line x + 2 = 0 coincides with one of the lines represented by the equation x2 + 2xy + 4y + k = 0, then prove that k = - 4. 


If equation ax2 - y2 + 2y + c = 1 represents a pair of perpendicular lines, then find a and c.


Find k if the slope of one of the lines given by 3x2 + 4xy + ky2 = 0 is three times the other.


The combined equation of the lines through origin and perpendicular to the pair of lines 3x2 + 4xy − 5y2 = 0 is ______


The joint equation of pair of straight lines passing through origin and having slopes `(1 + sqrt2) and (1/(1 + sqrt2))` is ______.


The equation of line passing through the midpoint of the line joining the points (-1, 3, -2) and (-5, 3, -6) and equally inclined to the axes is ______.


The joint equation of pair of lines having slopes `1+sqrt2` and `1-sqrt2` and passing through the origin is ______.


The joint equation of pair of lines having slopes 2 and 5 and passing through the origin is ______.


The combined equation of the lines which pass through the origin and each of which makes an angle of 30° with the line 3x + 2y – 11 = 0 is ______.


Write the separate equations of lines represented by the equation 5x2 – 9y2 = 0


Find the combined equation of the pair of lines passing through the origin and perpendicular to the lines represented by 3x2 + 2xy – y2 = 0.


Find the combined equation of y-axis and the line through the origin having slope 3.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×