Algebra 1 / Unit 8: Polynomials and Factoring
8.1 Adding and Subtracting Polynomials
Notes
A polynomial is a sum of terms like $3x^2$, $-5x$ and 7. Its degree is the highest exponent.
- Write polynomials in standard form: highest degree first, like $4x^3 - x^2 + 6$.
- Add: combine like terms.
- Subtract: distribute the negative to every term of the second polynomial, then combine.
Practice
What is the degree of $5x^2 - 3x^4 + x - 9$?
The highest exponent is 4.
$(3x^2 + 2x - 5) + (x^2 - 6x + 8) =$
$3x^2 + x^2$, $2x - 6x$, $-5 + 8$.
$(5y^2 - y + 4) - (2y^2 + 3y - 1) =$
$5y^2 - y + 4 - 2y^2 - 3y + 1$.
Ready for more? Take the Unit 8 test.