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100 points for $49 worth of Veritas practice GMATs FREE VERITAS PRACTICE GMAT EXAMS Earn 10 Points Per Post Earn 10 Points Per Thanks Earn 10 Points Per Upvote Two line l and k intersect at a point (4, 3). Is the product This topic has 1 expert reply and 0 member replies Top Member Two line l and k intersect at a point (4, 3). Is the product Timer 00:00 Your Answer A B C D E Global Stats Difficult Two line l and k intersect at a point (4, 3). Is the product of their slopes -1? (1) x intercepts of line l and k are positive (2) y intercept of line l and k are negative OA B Source: Princeton Review GMAT/MBA Expert GMAT Instructor Joined 09 Oct 2010 Posted: 1295 messages Followed by: 29 members Upvotes: 59 Top Reply BTGmoderatorDC wrote: Two line l and k intersect at point (4, 3). Is the product of their slopes -1? (1) x intercepts of line l and k are positive (2) y intercept of line l and k are negative Source: Princeton Review This one is tricky... nice! $\left( {4,3} \right)\,\, \in \,\,\,\left( {{\text{lin}}{{\text{e}}_{\,l}}\,\, \cap \,\,\,{\text{lin}}{{\text{e}}_{\,k}}} \right)$ ${\text{slop}}{{\text{e}}_{\,l}}\,\, \cdot \,\,\,{\text{slop}}{{\text{e}}_{\,k}}\,\,\,\mathop = \limits^? \,\,\, - 1$ (1) Insufficient. We present a GEOMETRIC BIFURCATION in the image attached. (2) We know line l and line k must have positive slopes (!), therefore the product of their slopes is positive (and not equal to -1)! The right answer is therefore __(B)___ . This solution follows the notations and rationale taught in the GMATH method. Regards, Fabio. _________________ Fabio Skilnik :: GMATH method creator ( Math for the GMAT) English-speakers :: https://www.gmath.net Portuguese-speakers :: https://www.gmath.com.br • Free Veritas GMAT Class Experience Lesson 1 Live Free Available with Beat the GMAT members only code • Get 300+ Practice Questions 25 Video lessons and 6 Webinars for FREE Available with Beat the GMAT members only code • Free Trial & Practice Exam BEAT THE GMAT EXCLUSIVE Available with Beat the GMAT members only code • Magoosh Study with Magoosh GMAT prep Available with Beat the GMAT members only code • Award-winning private GMAT tutoring Register now and save up to$200

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