7.7+Subtracting+Polynomials

Section 7.7 - Subtracting Polynomials


The key to understanding subtraction of polynomials is to see that you are subtracting all of the second polynomial -- each term in the polynomial is being subtracted. If you just drop the parentheses, you will be subtracting that first term (2y to the fourth), but you need to subtract each term in the second polynomial. Subtracting a negative number is actually adding, right?

The simplest way to do this is just to "distribute" the negative sign to each term in the second polynomial. Essentially you will just be changing the signs -- if it was positive, it is now negative, if it was negative, it becomes positive. After changing the signs, combine like terms just like you do when adding polynomials.



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 * Chapter Seven Practice Problems**

**Where to from here?**
7.1 Negative Exponents 7.2 Product Rule 7.3 Power Rule 7.4 Quotient Rule 7.5 Defining Polynomials 7.6 Adding Polynomials 7.7 Subtracting Polynomials 7.8 Multiplying Polynomials 7.9 Dividing Polynomials Chapter Seven Summary Chapter Seven Homework