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Adding and Subtracting Rational Expressions  Problem 8
Alissa Fong
Alissa Fong
MA, Stanford University
Teaching in the San Francisco Bay Area
Alissa is currently a teacher in the San Francisco Bay Area and Brightstorm users love her clear, concise explanations of tough concepts
When we first learn about common denominators, we use the idea of the LCM, or least common multiple. For example, if you were asked to do 1/2  1/6, a common denominator that would work is 12, but it's not the least common denominator (which would be 6). Using the least common denominator simplifies our work later. Here, we apply that idea to finding the LCM of monomials, binomials, and trinomials: we could technically multiply them to find a multiple that would work, but often, the least common multiple will make our work easier in the long run.
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Alissa Fong
M.A. in Secondary Mathematics, Stanford University
B.S., Stanford University
Alissa has a quirky sense of humor and a relatable personality that make it easy for students to pay attention and understand the material. She has all the math tips and tricks students are looking for.
Your tutorials are good and you have a personality as well. I hope you have more advanced college level stuff, because I like the way you teach.”
Thanks alot for such great lectures... I never found learning this easier ever before... keep up the great work.... :)”
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Sample Problems (9)
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Adding and Subtracting Rational Expressions
Problem 1 6,349 viewsSimplify:
4 + 2 7 + 14x 5 + 10x 
Adding and Subtracting Rational Expressions
Problem 2 5,305 viewsSimplify:
2 − x − 3 x − 2 x² + 2x + 4 x³ − 8 
Adding and Subtracting Rational Expressions
Problem 3 4,830 viewsSimplify:
4b − 3b b² + 6b + 5 b² + 5b + 4 
Adding and Subtracting Rational Expressions
Problem 4 1,102 views 
Adding and Subtracting Rational Expressions
Problem 5 1,069 views 
Adding and Subtracting Rational Expressions
Problem 6 1,129 views 
Adding and Subtracting Rational Expressions
Problem 7 1,118 views 
Adding and Subtracting Rational Expressions
Problem 8 986 views 
Adding and Subtracting Rational Expressions
Problem 9 1,078 views
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