How Do You Subtract Two Rational Expressions with Different Denominators?

How Do You Subtract Two Rational Expressions with Different Denominators?

Note:

Subtracting rational expressions? Don't have common denominators? No problem! Find the least common denominator (LCD) and change each rational expression into an equivalent expression with that LCD. Once you have common denominators, you're ready to subtract and simplify! Watch it all in this tutorial!

Keywords:

  • problem
  • rational expression
  • fraction
  • algebraic fraction
  • polynomial
  • subtract
  • difference
  • subtract fractions
  • different denominator
  • unequal denominator
  • simplify
  • simplest form
  • subtract polynomials
  • lcd
  • lowest common denominator
  • numerator
  • denominator

Background Tutorials

  • Identify parts of an expression using mathematical terms (sum, term, product, factor, quotient, coefficient); view one or more parts of an expression as a single entity.

      • What's a Term?What's a Term?

      What's a Term?

      Polynomials are those expressions that have variables raised to all sorts of powers and multiplied by all types of numbers. When you work with polynomials you need to know a bit of vocabulary, and one of the words you need to feel comfortable with is 'term'. So check out this tutorial, where you'll learn exactly what a 'term' in a polynomial is all about.

  • Interpret parts of an expression, such as terms, factors, and coefficients.

      • What's a Factor?What's a Factor?

      What's a Factor?

      Factors are a fundamental part of algebra, so it would be a great idea to know all about them. This tutorial can help! Take a look!

  • Use the structure of an expression to identify ways to rewrite it.

  • Understand that polynomials form a system analogous to the integers, namely, they are closed under the operations of addition, subtraction, and multiplication; add, subtract, and multiply polynomials.

      • What's FOIL?What's FOIL?

      What's FOIL?

      The FOIL method. No, not aluminum foil! The FOIL method stands for First, Outer, Inner, and Last. It's a popular way multiply two binomials together. This tutorial makes the FOIL method a breeze!

  • Understand that rational expressions form a system analogous to the rational numbers, closed under addition, subtraction, multiplication, and division by a nonzero rational expression; add, subtract, multiply, and divide rational expressions.

      • What's a Rational Expression?What's a Rational Expression?

      What's a Rational Expression?

      Got a fraction with a polynomial in the numerator and denominator? You have a rational expression! Learn about rational expressions in this tutorial.

Further Exploration

  • Understand that rational expressions form a system analogous to the rational numbers, closed under addition, subtraction, multiplication, and division by a nonzero rational expression; add, subtract, multiply, and divide rational expressions.

  • Create equations and inequalities in one variable and use them to solve problems. Include equations arising from linear and quadratic functions, and simple rational and exponential functions.

      • How Do You Solve a Word Problem with a Rational Equation?How Do You Solve a Word Problem with a Rational Equation?

      How Do You Solve a Word Problem with a Rational Equation?

      This tutorial provides a great real world application of math! This tutorial shows you how to take the information given in a word problem and turn it into a rational equation. Then, you'll see how to solve that equation and get your answer!