What is the degree of the polynomial 2x − x² + 4x³?
Unit 12 · Polynomials, Modeling & Comparison
Polynomial Operations
Combine like terms to add/subtract. Multiply with the distributive property (or a table). Degree adds when multiplying monomials.
Notes
Like terms only
3x² and 5x² combine; 3x² and 5x do not. Subtracting a polynomial means distributing the minus to every term.
Vocabulary
polynomial
A sum of terms of the form ax^n where n is a whole number.
Example: 4x³ − x + 7 is a cubic polynomial.
Worked examples
Try the prompt first. The steps stay folded until you ask to see them.
Multiply
(x + 3)(x − 5)
Common errors
Watch for
Writing (x + 3)² = x² + 9
The middle term 2·x·3 is missing.
Fix: Always write (x + 3)(x + 3).
Guided practice
Submit each answer to check it. The key is not shown until you do.
The expression −2(x² − 2x + 1) + (3x² + 3x − 5) is equivalent to
Which expression is equivalent to (x − 5)(2x + 7) − (x + 5)?
Intervention
Use an area model (box method) for every product.
Enrichment
Explain why the product of two linear factors is quadratic.
Explain your reasoning
Sentence starters · Notice and Wonder · Three Reads · Think-Pair-Share · Compare and Connect · Math Talk · Stronger and Clearer Each Time
- I combined … because they are like terms.