English

Find the Equation of the Line Passing Through the Point (2, 2) and Cutting off Intercepts on the Axes Whose Sum is 9.

Advertisements
Advertisements

Question

Find the equation of the line passing through the point (2, 2) and cutting off intercepts on the axes whose sum is 9.

Answer in Brief
Advertisements

Solution

The equation of the line with intercepts a and b is \[\frac{x}{a} + \frac{y}{b} = 1\] .

Here, a + b = 9  
\[\Rightarrow b = 9 - a\] ... (1)
The line passes through (2, 2).

∴ \[\frac{2}{a} + \frac{2}{b} = 1\]  ... (2)
From equations (1) and (2)

\[\frac{2}{a} + \frac{2}{9 - a} = 1\]

\[ \Rightarrow 18 - 2a + 2a = 9a - a^2 \]

\[ \Rightarrow a^2 - 9a + 18 = 0\]

\[ \Rightarrow \left( a - 3 \right)\left( a - 6 \right) = 0\]

\[ \Rightarrow a = 3, 6\]

For a = 3, b = 9  \[-\] 3 = 6

For a = 6, b = 9  \[-\] 6 = 3

Thus, the equation of the line is

\[\frac{x}{3} + \frac{y}{6} = 1 \text { or }\frac{x}{6} + \frac{y}{3} = 1\]

\[ \Rightarrow 2x + y = 6 \text { or } x + 2y = 6\]

shaalaa.com
Equations of Line in Different Forms - Equation of Family of Lines Passing Through the Point of Intersection of Two Lines
  Is there an error in this question or solution?
Chapter 23: The straight lines - Exercise 23.6 [Page 47]

APPEARS IN

R.D. Sharma Mathematics [English] Class 11
Chapter 23 The straight lines
Exercise 23.6 | Q 14 | Page 47

RELATED QUESTIONS

Find the equation of the line parallel to x-axis and passing through (3, −5).


Find the equation of the line parallel to x-axis and having intercept − 2 on y-axis.


Draw the lines x = − 3, x = 2, y = − 2, y = 3 and write the coordinates of the vertices of the square so formed.


Find the equation of the straight line passing through the point (6, 2) and having slope − 3.


Find the equation of the line passing through (0, 0) with slope m.


Find the equation of the straight line passing through (3, −2) and making an angle of 60° with the positive direction of y-axis.


Find the equation of the straight line which divides the join of the points (2, 3) and (−5, 8) in the ratio 3 : 4 and is also perpendicular to it.


Find the equation of the straight lines passing through the following pair of point :

(a cos α, a sin α) and (a cos β, a sin β)


By using the concept of equation of a line, prove that the three points (−2, −2), (8, 2) and (3, 0) are collinear.


The owner of a milk store finds that he can sell 980 litres milk each week at Rs 14 per liter and 1220 liters of milk each week at Rs 16 per liter. Assuming a linear relationship between selling price and demand, how many liters could he sell weekly at Rs 17 per liter.


Find the equation to the straight line cutting off intercepts − 5 and 6 from the axes.


Find the equation of the straight line which passes through (1, −2) and cuts off equal intercepts on the axes.


Find the equation to the straight line which cuts off equal positive intercepts on the axes and their product is 25.


Find the equation of the line which passes through the point (− 4, 3) and the portion of the line intercepted between the axes is divided internally in the ratio 5 : 3 by this point. 


Find the equation of the line, which passes through P (1, −7) and meets the axes at A and Brespectively so that 4 AP − 3 BP = 0.


Find the equation of the straight line which passes through the point P (2, 6) and cuts the coordinate axes at the point A and B respectively so that \[\frac{AP}{BP} = \frac{2}{3}\] .


Find the equations of the straight lines each of which passes through the point (3, 2) and cuts off intercepts a and b respectively on X and Y-axes such that a − b = 2.


Find the equations of the straight lines which pass through the origin and trisect the portion of the straight line 2x + 3y = 6 which is intercepted between the axes.


The straight line through P (x1, y1) inclined at an angle θ with the x-axis meets the line ax + by + c = 0 in Q. Find the length of PQ.


If the straight line \[\frac{x}{a} + \frac{y}{b} = 1\] passes through the point of intersection of the lines x + y = 3 and 2x − 3y = 1 and is parallel to x − y − 6 = 0, find a and b.


Find the equation of a line passing through the point (2, 3) and parallel to the line 3x − 4y + 5 = 0.


Find the equation of a line drawn perpendicular to the line \[\frac{x}{4} + \frac{y}{6} = 1\] through the point where it meets the y-axis.


Find the length of the perpendicular from the point (4, −7) to the line joining the origin and the point of intersection of the lines 2x − 3y + 14 = 0 and 5x + 4y − 7 = 0.


Find the distance of the point (1, 2) from the straight line with slope 5 and passing through the point of intersection of x + 2y = 5 and x − 3y = 7.


Find the equation of the straight lines passing through the origin and making an angle of 45° with the straight line \[\sqrt{3}x + y = 11\].


Find the equations to the straight lines which pass through the origin and are inclined at an angle of 75° to the straight line \[x + y + \sqrt{3}\left( y - x \right) = a\].


The equation of one side of an equilateral triangle is x − y = 0 and one vertex is \[(2 + \sqrt{3}, 5)\]. Prove that a second side is \[y + (2 - \sqrt{3}) x = 6\]  and find the equation of the third side.


Find the equations of the two straight lines through (1, 2) forming two sides of a square of which 4x+ 7y = 12 is one diagonal.


Find the equations of the lines through the point of intersection of the lines x − 3y + 1 = 0 and 2x + 5y − 9 = 0 and whose distance from the origin is \[\sqrt{5}\].


If the diagonals of the quadrilateral formed by the lines l1x + m1y + n1 = 0, l2x + m2y + n2 = 0, l1x + m1y + n1' = 0 and l2x + m2y + n2' = 0 are perpendicular, then write the value of l12 − l22 + m12 − m22.


Write the equation of the line passing through the point (1, −2) and cutting off equal intercepts from the axes.


The equation of the straight line which passes through the point (−4, 3) such that the portion of the line between the axes is divided internally by the point in the ratio 5 : 3 is


The inclination of the straight line passing through the point (−3, 6) and the mid-point of the line joining the point (4, −5) and (−2, 9) is


If a, b, c are in A.P., then the straight lines ax + by + c = 0 will always pass through ______.


Equation of the line passing through the point (a cos3θ, a sin3θ) and perpendicular to the line x sec θ + y cosec θ = a is x cos θ – y sin θ = a sin 2θ.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×