Data Sufficiency- 700 level

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Data Sufficiency- 700 level

by kinshuk97gupta » Thu Jul 02, 2020 5:50 am
Does the point (p, q) lie on the line y = mx + c (p, m, and c are non-zero)?

(1) The line y = mx – c passes through the point (p, q).
(2) The line y = –mx + c passes through the point (p, q).

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Re: Data Sufficiency- 700 level

by rvgmat12 » Fri Oct 01, 2021 11:28 pm
(1) The line y = mx – c passes through the point (p, q).
Line y=mx-c is parallel to y=mx+c but they are same when c=0 which is not the case.
so no intersection point exists.
If (p,q) lie on line y=mx+c => (p,q) does not lie on y=mx-c
SUFFICIENT

(2) The line y = –mx + c passes through the point (p, q).
Intersection point of y=mx+c and y=-mx+c is (0,c)
Since p<>0 indicates that (p,q) is not the intersection point of lines y=mx+c and y=-mx+c.
If (p,q) lie on line y=mx+c => (p,q) does not lie on y=-mx+c
SUFFICIENT

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