Teacher2Teacher Q&A #9409

Teachers' Lounge Discussion: Solving algebraic equations

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From: John

To: Teacher2Teacher Public Discussion
Date: 2005061602:01:04
Subject: Re:find formula for equation and answer

Turn the two fractions into one fraction and set numerator and denominator equal to each other. Solve the system. Like this Given: 1/a +1/b = 37/180 Multiply 1/a by "b" and 1/b by "a" yielding (a+b)/ ab =37/180 Set numerator and denominators equal to each other: a+b = 37 and ab = 180 so, a=180/b Substitute into other equation: b + (180/b) = 37 Multiplying by b and bringing everything to left b^2 -37b + 180 = 0 Using quadratic formula: b= (37 + sqr(649))/2 and a= 37-((37 + sqr(649))/2 The quad. almost factors so I wonder if there is an error in the fraction 37/180

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