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 October 14th, 2012, 06:37 PM #1 Newbie   Joined: Oct 2012 Posts: 1 Thanks: 0 Find length of sides of quadrilateral; write equation Hello all, I have a seemingly simple question. I have a quadrilateral with sides (starting with the left side, moving clockwise)7-x), (x+2), (2x-1), (x-3). a) write an equation for the perimeter and simplify: that's easy, and done. This ends up as 3x+5 b) Find the length of all sides. Using the result from above, 3x+5 = -5/3, and would give one of the sides a -negative answer. I assume one cannot have a negative length? Your thoughts and help will be greatly appreciated. Kindly, David Dudek
 October 14th, 2012, 07:07 PM #2 Global Moderator     Joined: Oct 2008 From: London, Ontario, Canada - The Forest City Posts: 7,974 Thanks: 1156 Math Focus: Elementary mathematics and beyond Re: Find length of sides of quadrilateral; write equation You've got an expression, 3x + 5, not an equation. The result of -5/3 assumes 3x + 5 = 0, when it should be 3x + 5 = P, where P is the perimeter. Using this we have x = (P - 5)/3. Can you continue from there? Note: P must be less than 26 units. Do you see why?
October 14th, 2012, 07:49 PM   #3
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Re: Find length of sides of quadrilateral; write equation

Quote:
 Originally Posted by David Dudek (7-x), (x+2), (2x-1), (x-3).
side 7-x: x < 7
side x-3: x > 3
So x = 4 or 5 or 6

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