Addition and Subtraction of Polynomials

Question

Subtract the polynomials:

(5y2+7y+2)−(8y2−6y+9)=

Answer 1

(5y2 + 7y + 2) − (8y2 − 6y + 9) =

The negative sign affects everything inside the parentheses. Thus, this negative sign changes all of the signs to their (additive) opposites:

(5y2 + 7y + 2) − 8y2 + 6y - 9 = 5y^2 + 7y + 2− 8y2 + 6y - 9

Using the commutative law of addition*, rearrange the terms so that like terms are next to each other

5y^2 -8y^2 + 7y + 6y + 2 - 9

*(a+b = b+a)

Next combine the like terms

-3y^2 + 13y -7

and you are done.

Answer 2

Hi Genesis,

If you distribute the negative on the subtrahend (the expression inside the right parenthesis), you get: 5y²+7y+2-8y²+6y-9.

Now, combine like terms: -3y²+13y-7