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 April 6th, 2018, 12:21 PM #1 Newbie   Joined: Apr 2018 From: Chile Posts: 3 Thanks: 0 Function problem If you can help me please, the correct answer is E, but if you can explain why the 3 sentences are correct I would appreciate it very much. Thanks. Funciones.jpg Last edited by skipjack; April 6th, 2018 at 01:41 PM. April 6th, 2018, 02:53 PM #2 Global Moderator   Joined: Dec 2006 Posts: 21,105 Thanks: 2324 The diagram is badly drawn. It should appear more like as shown below. ABgraph.PNG OB has slope 1/2 and OA has slope -2, where A is the point (-3, 6) and B is the point (6, 3). April 27th, 2018, 05:44 AM #3 Math Team   Joined: Jan 2015 From: Alabama Posts: 3,264 Thanks: 902 I agree that the picture is badly drawn- or at least badly labeled. Also, we must assume that OA and OB are straight lines, which is not stated. IF OA is a straight line through (0, 0) and (-2, 4) then f(x) = -2x for x < 0 so that f(-3) = -2(-3) = 6. IF OB is a straight line through (0, 0) and (4, 2) then f(x) = x/2 for x > 0 so that f(6) = 6/2 = 3. Knowing that A = (-3, 6) and that B = (6, 3) we can calculate the lengths of the sides: $\displaystyle OA= \sqrt{(-3)^2+ 6^2}= \sqrt{45}= 3\sqrt{5}$, $\displaystyle OB= \sqrt{6^2+ 3^2}= \sqrt{45}= 3\sqrt{5}$. Triangle AOB is an equilateral triangle with sides OB and OA congruent. Last edited by skipjack; April 27th, 2018 at 07:40 AM. April 27th, 2018, 07:33 AM #4 Global Moderator   Joined: Dec 2006 Posts: 21,105 Thanks: 2324 I assume you mean "isosceles right triangle", not "equilateral triangle". May 26th, 2018, 04:03 AM #5 Math Team   Joined: Jan 2015 From: Alabama Posts: 3,264 Thanks: 902 Yes, thank you. Tags function, problem Thread Tools Show Printable Version Email this Page Display Modes Linear Mode Switch to Hybrid Mode Switch to Threaded Mode Similar Threads Thread Thread Starter Forum Replies Last Post tsl182forever8 Applied Math 3 November 26th, 2012 10:42 PM mathwiztheo Algebra 2 November 19th, 2012 03:58 AM fcs_florin Algebra 5 November 16th, 2010 12:03 PM murkr Algebra 1 April 19th, 2010 05:56 PM spank Algebra 2 February 27th, 2008 12:52 PM

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