Algebra 1 · Arithmetic with Polynomials

Multiply simple polynomials

Multiply simple polynomials.

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What you’ll learn

Multiply simple polynomials.

Key idea

Keep all six products before combining cubic, square, linear and constant powers.

Distribute both linear-factor terms across all three quadratic addends, then combine powers up to degree three.

Worked example

Enter the exact value or ordered values in the format requested below.

Expand (x²-6x-5)(x+2); enter collected polynomial of degree three.

  1. Multiply quadratic by x to obtain x³-6x²-5x; multiply by 2 to obtain 2x²-12x-10.
  2. Combine matching powers to get x³-4x²-17x-10; missing b gives square coefficient b+(2)=-4 and linear coefficient -5+2b=-17.

Answer: x³-4x²-17x-10

Quick Check

Evaluate a worked attempt at multiply simple polynomials, identify the first invalid step, and provide the correction.

Expand (x²-6x-2)(x-6): Step 1 multiplies by x to get x³-6x²-2x. Step 2 multiplies by -6 but omits -6x², yielding x³-6x²+34x+12. Locate the first invalid step and repair the cubic.

Choose one answer

Show a hint

Distribute both terms of the linear factor across every quadratic term.