In the xy-plane, does the line in question y=3x+2 contain the point (r,s)?
(1) (3r+2-s)(4r+9-s)=0
(2) (4r-6-s)(3r+2-s)=0
OA C
Can anyone explain in detail?
Coordinate geomtry
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If (r,s) lie on the line then it has to satisfy the equation y=3x+2 contain the point (r,s)selango wrote:In the xy-plane, does the line in question y=3x+2 contain the point (r,s)?
(1) (3r+2-s)(4r+9-s)=0
(2) (4r-6-s)(3r+2-s)=0
OA C
Can anyone explain in detail?
So it becomes like: s= 3r+2
Combining st 1 & st2 :
(3r+2-s) (4r+9-s) +(4r-6-s)(3r+2-s)=0
(3r+2-s) {(4r+9-s) +(4r-6-s) }=0
(3r+2-s) {15} =0
--->(3r+2-s) =0
---> 3r+2 =s
pick C
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When asked if a point is on a certain line, test whether or not it satisfies the equation of the line.
The question can actually be summarized to : Is s = 3r + 2
1. (3r + 2 - s)*(4r + 9 - s) = 0
=> 3r + 2 - s = 0 OR 4r + 9 - s =0
=> s = 3r + 2 (on the line)OR s = 4r + 9 (not on the line)
INSUFFICIENT
2. (4r - 6 - s)*(3r + 2 - s) = 0
=>4r - 6 - s = 0 OR 3r + 2 - s = 0
=> s = 4r + 6(on the line)Or s = 3r + 2(not on the line)
INSUFFICIENT
Both 1 and 2.
The common solution is only s = 3r + 2 (on the line)... SUFFICIENT
Pick C.
The question can actually be summarized to : Is s = 3r + 2
1. (3r + 2 - s)*(4r + 9 - s) = 0
=> 3r + 2 - s = 0 OR 4r + 9 - s =0
=> s = 3r + 2 (on the line)OR s = 4r + 9 (not on the line)
INSUFFICIENT
2. (4r - 6 - s)*(3r + 2 - s) = 0
=>4r - 6 - s = 0 OR 3r + 2 - s = 0
=> s = 4r + 6(on the line)Or s = 3r + 2(not on the line)
INSUFFICIENT
Both 1 and 2.
The common solution is only s = 3r + 2 (on the line)... SUFFICIENT
Pick C.
~Abhay
Believe those who are seeking the truth. Doubt those who find it. -- Andre Gide
Believe those who are seeking the truth. Doubt those who find it. -- Andre Gide