My Math Forum The equation of all parabolas given a vertex and a point
 User Name Remember Me? Password

 Pre-Calculus Pre-Calculus Math Forum

 August 26th, 2017, 08:47 PM #1 Newbie   Joined: Aug 2017 From: USA Posts: 1 Thanks: 0 The equation of all parabolas given a vertex and a point "Find the equation of all parabolas having vertex (-2, -3), passing through (2, 1), and whose directrix is horizontal or vertical." How do you find the one equation that would satisfy the given information? My method of solving left me with 2 equations (one for each of the vertical and horizontal directrix).
 August 26th, 2017, 11:42 PM #2 Senior Member     Joined: Sep 2015 From: Southern California, USA Posts: 1,410 Thanks: 715 I can't see how you would have the same equation for both orientations of the parabola. One would be quadratic in $x$ the other would be quadratic in $y$
 August 27th, 2017, 04:17 AM #3 Math Team   Joined: Jan 2015 From: Alabama Posts: 2,647 Thanks: 680 A vertical parabola is a function of x but not y. A horizontal parabola is a function of y but not x. There cannot be a formula in x and y only that gives both.

 Tags equation, parabolas, point, vertex

 Thread Tools Display Modes Linear Mode

 Similar Threads Thread Thread Starter Forum Replies Last Post GIjoefan1976 Algebra 3 June 2nd, 2017 02:41 PM GIjoefan1976 Algebra 7 April 28th, 2017 04:17 AM elim Geometry 5 September 19th, 2014 02:11 PM sallyyy Algebra 6 November 14th, 2010 12:24 PM varunnayudu Trigonometry 3 December 1st, 2009 10:13 PM

 Contact - Home - Forums - Cryptocurrency Forum - Top