og11 #78

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Source: — Data Sufficiency |

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by papgust » Mon Nov 02, 2009 1:11 am
I think the answer is C,

Individually you cannot get the length of QR or PR.
Combining,
(a,b) is (-2,-1) and (c,d) is (3,4)

Length of PR/Length of QR = 5/5 = 1 which answers the question.

Hence C. Whats the OA?

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by uptowngirl92 » Mon Nov 02, 2009 5:09 am
Could somebody show the workings?

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by life is a test » Mon Nov 02, 2009 6:54 am
uptowngirl92 wrote:Could somebody show the workings?
the question is asking if pr = qr or is the triangle shown is a right angle isoceles triangle (in which case two of the states lines will have equal lengths.

to know the lengths of the lines you need the x,y coordinates for both points; this is what (a,b) and (c,d) give hence you can calculate the movement along the x-axis which is from -2 to 3 -> this is 5 units of movement and similarly the y coords go from -1 to 4 which is also a 5 units movement along the y-axis.

this means both lines have equal length and hence the ratio of their lengths = 1.

hope that helps.