wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

Which of the following lines is concurrent with the lines 3x+4y+6=0 and 6x+5y+9=0?


A

2x+3y+5=0

No worries! We‘ve got your back. Try BYJU‘S free classes today!
B

3x+3y+5=0

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
C

7x+9y+3=0

No worries! We‘ve got your back. Try BYJU‘S free classes today!
D

None of these

No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is B

3x+3y+5=0


Explanation for the correct option: b) 3x+3y+5=0.

Step 1:Find the point of intersection of 3x+4y+6=0 and 6x+5y+9=0.

The lines which intersect each other at exactly one point are the concurrent lines.

3x+4y=-6i6x+5y=-9ii

Multiply i by 2.

6x+8y=-12i

6x+5y=-9ii

Subtract ii from i

3y=-3

y=-1

Put y=-1in i.

3x+4-1=-6

3x-4=-6

3x=-2

x=-23

The point of intersection is -23,-1.

Step 2: Put the values of x and y in 3x+3y+5=0.

3x+3y+5=0

3-23+3-1+5=0

-2-3+5=0.

Since the left-hand side is equal to the right-hand side, it is concurrent.

Hence, the correct answer is option b) 3x+3y+5=0.

Explanation of incorrect options:

Option (A)

Putting x=-23 and y=-1 in the equation 2x+3y+5=0

2-23+3-1+5=0

-43-3+5=0

23=0

Which is incorrect.

Option (C)

Putting x=-23 and y=-1 in the equation 7x+9y+3=0

7-23+9-1+3=0

-143-9+5=0

-263=0

Which is incorrect.

Hence, the correct answer is option b) 3x+3y+5=0.


flag
Suggest Corrections
thumbs-up
2
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Applications
MATHEMATICS
Watch in App
Join BYJU'S Learning Program
CrossIcon