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March 9th, 2011, 03:46 PM  #1 
Newbie Joined: Mar 2011 Posts: 1 Thanks: 0  points of intersections
Hey guys I know this is going to seem like a retarted question but here goes. determine the point of intersection of f(x)=5+?x+1 and g(x)=x+1 when you set them equal the equation it ends in is 0=x^29x+15 how do i resolve for the x and y values for the point of intersection? 
March 9th, 2011, 03:58 PM  #2 
Senior Member Joined: Jul 2010 From: St. Augustine, FL., U.S.A.'s oldest city Posts: 12,211 Thanks: 521 Math Focus: Calculus/ODEs  Re: points of intersections
Are you sure you have f(x) copied correctly? I ask because I get a different equation in x when I equate f and g, and it seems odd it would be given with like terms left to combine. My best guess is that you are given: Equate f and g: Subtract 5 from both sides: Square both sides, keeping in mind extraneous solutions may be introduced, if they are less than 4 (a square root cannot be negative): Write in standard quadratic form: Apply quadratic formula: Discard root less than 4: Now, for the ycoordinate use either or . 
March 10th, 2011, 08:32 AM  #3  
Math Team Joined: Dec 2006 From: Lexington, MA Posts: 3,267 Thanks: 408  Re: points of intersections Hello, functionman! Quote:
 
March 10th, 2011, 08:46 AM  #4 
Senior Member Joined: Jul 2010 From: St. Augustine, FL., U.S.A.'s oldest city Posts: 12,211 Thanks: 521 Math Focus: Calculus/ODEs  Re: points of intersections
I guess your years as a professor has better equipped you to translate what people mean to write vs. what they actually write! 

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