Quadratic EquationDate: 04/08/97 at 18:40:09 From: Aaron Hubert Subject: Solving a system of two equations I have a word problem that I haven't even started because I don't understand it. "The sum of two numbers is 15 and their product is 54. Find the numbers using a quadratic equation." Any help would be deeply appreciated. Date: 04/13/97 at 12:20:51 From: Doctor Steven Subject: Re: Solving a system of two equations You have those two equations to solve for. Say the first number is x, and the second number is y. Then: x + y = 15 x * y = 54. Using the first equation: y = 15 - x. Plug this into the second equation to get x*(15 - x) = 54. Simplify the equation: 15x - x^2 = 54. Simplify more: x^2 - 15x + 54 = 0. Solve for x using the quadratic equation. Then y = 15 - x. Hope this helps. -Doctor Steven, The Math Forum Check out our web site! http://mathforum.org/dr.math/ |
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