Recall that slope = (y2 - y1)/(x2-x1). So the slope is (u - (-s))/(t-r) = (u+s)/(t-r).
(1) r > t. Subtract r from both sides and get 0 > t - r . This tells us that the denominator is negative. Numerator could be positive or negative so cannot determine the sign of the slope. INSUFFICIENT.
(2). u > -s. Add s to both sides and get u + s > 0. This tells us that the numerator is positive. The denominator could be positive or negative so we cannot determine the sign of the slope. INSUFFICIENT.
(1)+(2). (1) tells us that the denominator is negative and (2) tells us that the numerator is positive. So the slope is negative.
The answer is C.
Slope DS
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Source: Beat The GMAT — Data Sufficiency |
ok one question here.....
now since the negative co-ordinate is given a negative sign...then why cant the other co-ordinates tht are without sighs considered positive.
bcos if we consider them as positive then A is sufficient to answer.
now since the negative co-ordinate is given a negative sign...then why cant the other co-ordinates tht are without sighs considered positive.
bcos if we consider them as positive then A is sufficient to answer.
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mikeCoolBoy
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I think you're assuming that because s has a negative sign s is negative.
The question only says that the line L passes through points (r,-s) and (t,u)
statement 1 says that r > t
for example r = 3, t = 2, u = 2 and s = -3 gives a slope 1
while r = 3, t= 2, u = 2 and s = 3 gives a slope -5
so statement 1 is insufficient
The question only says that the line L passes through points (r,-s) and (t,u)
statement 1 says that r > t
for example r = 3, t = 2, u = 2 and s = -3 gives a slope 1
while r = 3, t= 2, u = 2 and s = 3 gives a slope -5
so statement 1 is insufficient
