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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.
Sample Problems (9)
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Adding and Subtracting Rational Expressions
Problem 1 6,814 viewsSimplify:
4 + 2 7 + 14x 5 + 10x 
Adding and Subtracting Rational Expressions
Problem 2 5,806 viewsSimplify:
2 − x − 3 x − 2 x² + 2x + 4 x³ − 8 
Adding and Subtracting Rational Expressions
Problem 3 5,363 viewsSimplify:
4b − 3b b² + 6b + 5 b² + 5b + 4 
Adding and Subtracting Rational Expressions
Problem 4 1,433 views 
Adding and Subtracting Rational Expressions
Problem 5 1,355 views 
Adding and Subtracting Rational Expressions
Problem 6 1,430 views 
Adding and Subtracting Rational Expressions
Problem 7 1,422 views 
Adding and Subtracting Rational Expressions
Problem 8 1,285 views 
Adding and Subtracting Rational Expressions
Problem 9 1,396 views
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