Algebra 1 · Seeing Structure in Expressions

Factor x² + bx + c

Factor x² + bx + c.

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What you’ll learn

Factor x² + bx + c.

Key idea

A monic binomial product has middle coefficient equal to its constants' sum and constant term equal to their product.

Both signed sum and product constraints must match; constant product alone is insufficient.

Worked example

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

Factor x²-12x+35 into two integer binomials. Enter their product rather than expanded polynomial.

  1. Signed constants must multiply to 35 and add to -12; -7×-5=35, -7+(-5)=-12.
  2. (x-7)(x-5) expands to x²-12x+35; pair 1,35 has the same constant product but middle coefficient 36, not -12.

Answer: (x-7)(x-5)

Quick Check

Evaluate a worked attempt at factor x² + bx + c, identify the first invalid step, and provide the correction.

Factor x²-3x-10: Step 1 seeks constants whose product is -10. Step 2 picks 1 and -10, writing (x+1)(x-10) without checking their sum. Locate the first invalid step and repair it.

Choose one answer

Show a hint

Use both signed product and sum constraints, not only one.