Q.

The combined equation of straight lines passing through point  −1,2 and each line makes intercepts on the coordinate axes whose product is

see full answer

Want to Fund your own JEE / NEET / Foundation preparation ??

Take the SCORE scholarship exam from home and compete for scholarships worth ₹1 crore!*
An Intiative by Sri Chaitanya

a

(x+y−1)(4x+y+2)=0

b

(x+y+1)(4x+y+2)=0

c

(x+y−1)(4x+y−2)=0

d

(x−y−1)(4x+y+2)=0

answer is A.

(Unlock A.I Detailed Solution for FREE)

Ready to Test Your Skills?

Check your Performance Today with our Free Mock Test used by Toppers!

Take Free Test

Detailed Solution

The equation of any line which makes x- intercept a and y- intercept b is  xa+yb=1Since the product of intercepts is equal to 1, one is the reciprocal of the other. It means a,1a  are intercepts of the line. Hence, the equation of the line can be written asxa+ay=1                                            ......(1) It is passing through the point  (-1,2)   −1a+2a=12a2−a−1=0 The roots of the equation are a=1,a=−12 Substitute a=1 in equation (1) It gives x+y−1=0 Substitute a=−12in equation (1) It gives −2x−12y=1−4x−y=24x+y+2=0 The combined equation of two lines is the product of both equationsTherefore, the combined equation of pair of lines is x+y−14x+y+2=0
Watch 3-min video & get full concept clarity
score_test_img

Get Expert Academic Guidance – Connect with a Counselor Today!

whats app icon