Adding Fractions in Algebra
Date: 2/9/96 at 21:53:5 From: Jason Lee Subject: Addition of fractions (monomial by binomial) Here's the problem : 2a + b a ------ + - a - b b Here's what I did, though I don't think it's right. There's probably an easier way. Cross multiply. And multiply the denominators. And I get : 2a + b^2 a^2 - b 2a + b^2 + a^2 - b -------- + ------- = ------------------ ???? a - b^2 a - b^2 a - b^2 And can I simplify if it is correct?
Date: 2/14/96 at 18:11:16 From: Doctor Byron Subject: Re: Addition of fractions (monomial by binomial) Hi, Jason. You seem to understand the basics of how to do this kind of problem well. In fact there is only a small error in your method. If you'll look further down in your letter, I'll point it out. >2a + b^2 a^2 - b 2a + b^2 + a^2 - b >-------- + ------- = ------------------ ???? > a - b^2 a - b^2 a - b^2 | |---Right here, you forgot to distribute the b to both terms when multiplying the denominators. Therefore, ab - b^2 should be the denominator in both cases. You also missed a similar distribution in the first numerator. You seem to have the idea of the method, however. And don't worry, even math doctors make those kind of mistakes. -Doctor Byron, The Math Forum
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