Algebra 1 · Arithmetic with Polynomials

Multiply binomials

Multiply binomials.

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What you’ll learn

Multiply binomials.

Key idea

Include both cross products and combine only like powers; first and last products alone are incomplete.

All four products contribute; include both signed cross terms and require expanded result.

Worked example

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

Expand (x-7)(x-5); enter collected polynomial.

  1. All four products are x², -5x, -7x, 35; cross terms sum to -12x.
  2. Collected result x²-12x+35; missing constant k obeys -7k=35 and -7+k=-12, giving k=-5.

Answer: x²-12x+35

Quick Check

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

Expand (x-5)(x+2): Step 1 obtains x² and constant -10. Step 2 omits both cross products, reporting x²-10. Locate the first invalid step and correct it.

Choose one answer

Show a hint

Enumerate every first-factor/second-factor term pair.