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Question 1155733: Find the equation of all lines passing through the point (6, -1) for which the
product of their x- and y-intercepts is 3
Found 2 solutions by MathLover1, greenestamps: Answer by MathLover1(20849) (Show Source): Answer by greenestamps(13200) (Show Source):
You can put this solution on YOUR website!
The solution by the other tutor is incomplete; there are two lines that satisfy the given conditions.
In her solution, she assumes that, since the product of the two intercepts is 3, one of the must be 3 and the other must be 1. That is not true.
Let the intercepts be (a,0) and (0,b).
The equation of the line is y = mx+b. We know
(1) 
(2) (6,-1) is on the line, so 
(3) 
Simplify (2) and substitute (3):



(4)
Substitute (4) in (3):




or 
ANSWERS:
b=-1/2 and ab=3 means a = -6; the intercepts are (-6,0) and (0,-1/2); the equation is y = (-1/12)x-1/2
b = 1 and ab=3 means a=3; the intercepts are (3,0) and (0,1); the equation is y = (-1/3)x+1
A graph....

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