Question
Question: The vertices of a triangle OBC are \(( 0,0 ) , ( - 3 , - 1 )\) and \(( - 1 , - 3 )\)respectively. ...
The vertices of a triangle OBC are (0,0),(−3,−1) and (−1,−3)respectively. Then the equation of line parallel to BC which is at 21unit distant from origin and cuts OB and OC, is.
A
2x+2y+2=0
B
2x+2y−2=0
C
2x−2y+2=0
D
None of these
Answer
2x+2y+2=0
Explanation
Solution
Gradient of BC=−1 and its equation is x+y+4=0. Therefore the equation of line parallel to BCis x+y+λ=0.Also it is 21unit distant from origin. Thus

Hence the required equation of line is 2x+2y+2=0.