Adding and Subtracting Monomials
Just as you can perform operations on numbers, you can perform operations on polynomials. To add or subtract polynomials, combine like terms.
Add or subtract.
Examples:
15m3 + 6m2 + 2m3 =
15m3 + 6m2 + 2m3 =
15m3 + 2m3 + 6 m2 =
17m3+ 6m2
3x2 + 5 - 7x2 + 12
3x2 + 5 - 7x2 + 12 =
3x2- 7x2 + 5 + 12 =
-4x2 + 17
0.9y5 - 0.4y5 + 0.5x5 + y5
0.9y5 - 0.4y5 + 0.5x5 + y5 =
0.9y5 - 0.4y5 + y5 + 0.5x5 =
1.5y5 + 0.5x5
2 x2y - x2y - x2y
2x2y - x2y - x2y =
2x2y - x2y - x2y
0
Forms of Solving Addition or Subtraction with Polynomials
Polynomials can be added in either vertical or horizontal form.
In vertical form, align the like terms and add:
In horizontal form, use the Associative and Commutative Properties to regroup and combine like terms:
Adding Polynomials
Add.
Examples:
(2x2 - x) + (x2 + 3x - 1)
(2x 2 - x) + (x2 + 3x - 1) =
(2x2 - x) + (x2 + 3x - 1) =
(2x2 + x2) + (-x + 3x) + (-1) =
3x2 + 2x – 1
(-2ab + b) + (2ab + a)
(-2ab + b) + (2ab + a) =
(-2ab + 2ab) + b + a =
0 + b + a = b + a
(4b5 + 8b) + (3b5 + 6b - 7b5 + b)
(4b5 + 8b) + (3b5 + 6b - 7b5 + b) =
15b
(20.2y2 + 6y + 5) + (1.7y2 - 8)
(20.2y2 + 6y + 5) + (1.7y2 - 8) =
21.9 y2 + 6y – 3
Subtracting Polynomials
To subtract polynomials, remember that subtracting is the same as adding the opposite. To find the opposite of a polynomial, you must write the opposite of each term in the polynomial: -(2x3 - 3x + 7) = -2x3 + 3x - 7
Subtract.
Examples:
(2x2 + 6) - (4x2) =
(2x2 + 6) + (-4x2) =
(2x2 + 6) + (-4x2) =
(2x2 - 4x2) +