88 Easy Algebra Step-by-Step
Addition and Subtraction of Monomials
Because variables are standing in for real numbers, you can use the proper-
ties of real numbers to perform operations with polynomials.
Addition and Subtraction of Monomials
- To add monomials that are like terms, add their numerical coeffi -
cients and use the sum as the coeffi cient of their common variable
component. - To subtract monomials that are like terms, subtract their numerical
coeffi cients and use the difference as the coeffi cient of their common
variable component. - To add or subtract unlike terms, indicate the addition or subtraction.
Problem Simplify.
a. −+ 10 xx+ 2525
b. 47 xy^23 xy^323
c. 9 xx^2233333 x^2 − 7 x^2
d. 25 + 25 x
e. 5 xx^22777
Solution
a. −+ 10 xx+ 2525
Step 1. Check for like terms.
−+ 10 xx+ 2525
− 10 x and 25 x are like terms.
Step 2. Add the numerical coeffi cients.
−+ 10 25 = 15
Step 3. Use the sum as the coeffi cient of x.
−+ 10 xx+ 2525 = 15 x
b. 47 xy^23 xy^323
Step 1. Check for like terms.
47 xy^23 xy^32
P
−+ 10 xx+ 2525 ≠ 15 x^2. In addition
and subtraction, the exponents
on the variables do not change.