Hi everyone... I'm hoping for some help with a logical and time efficient method of solving this one.
In the xyplane, region R consists of all the points (x,y) such that 2x + 3y <= 6. Is the point (r,s) in the region R?
(1) 3r + 2s = 6
(2) r <= 3 and s <= 2
OA: E
OG 12  DS 121
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 Posts: 3
 Joined: 27 Jan 2009
I don know how to draw the graph here.
But by the problem statement, graph wud luk like:
X axis having 3 as the intercept and Y axis having 2 as intercept and the region covered wud be towards the origin. Lets call this graph1.
By option 1 : X intercept is 2, Y intercept is 3 and the region is towards the origin(say graph2), thus covering both the areas, one inside the graph1 and outside as well. So cannot be determined.
By option 2: Check for point (2.5,1.5) the region is outside graph1, now check for point (0,0) and the region comes out to be inside graph1.
So cannot be determined.
Combining option 1 and 2: Draw X =3 and Y=2, combine with graph2 and still the graph lies both outside and inside graph1.
So answer is E
Doing it graphically took me 2 minutes.
But by the problem statement, graph wud luk like:
X axis having 3 as the intercept and Y axis having 2 as intercept and the region covered wud be towards the origin. Lets call this graph1.
By option 1 : X intercept is 2, Y intercept is 3 and the region is towards the origin(say graph2), thus covering both the areas, one inside the graph1 and outside as well. So cannot be determined.
By option 2: Check for point (2.5,1.5) the region is outside graph1, now check for point (0,0) and the region comes out to be inside graph1.
So cannot be determined.
Combining option 1 and 2: Draw X =3 and Y=2, combine with graph2 and still the graph lies both outside and inside graph1.
So answer is E
Doing it graphically took me 2 minutes.