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Adding and subtracting rational expressions

6 videos
7 skills
Well, rational expressions are just algebraic expressions formed by dividing one expression by another. In this tutorial, we'll see that, even though they may look hairy, adding and subtracting rational expressions involves most of what we know about adding and subtracting numeric fractions.

Adding and subtracting rational expressions 1

PRACTICE PROBLEMS
Adding and subtracting two expressions with common denominator and each of the form Ax/B or A/Bx.

Adding and subtracting rational expressions 2

PRACTICE PROBLEMS
Adding and subtracting expressions with a common denominator, where each is of the form (Ax+B)/(Cx+D).

Adding and subtracting rational expressions 3

PRACTICE PROBLEMS
Adding and subtracting multiple variable expressions with the same denominators where each is an expression containing up to two terms and four variables.

Adding and subtracting rational expressions 2

VIDEO 2:56 minutes
U11_L1_T3_we2 Adding and Subtracting Rational Expressions 2

Subtracting rational expressions

VIDEO 5:35 minutes
Subtracting Rational Expressions

Simplifying first for subtracting rational expressions

VIDEO 2:52 minutes
Simplifying First for Subtracting Rational Expressions

Adding and subtracting rational expressions 4

PRACTICE PROBLEMS
Adding and subtracting two expressions with different denominators, where each is of the form Ax/B or A/Bx.

Adding and subtracting rational expressions

VIDEO 8:15 minutes
Adding and Subtracting Rational Expressions

Adding and subtracting rational expressions 3

VIDEO 4:36 minutes
U11_L1_T3_we3 Adding and Subtracting Rational Expressions 3

Rationalizing denominators of expressions

VIDEO 4:58 minutes
Rationalizing Denominators of Expressions