Factoring Quadratics

Step-by-step factorization calculator and complete guide

Learn to factor quadratic equations using AC method, grouping, and special patterns. Our interactive calculator shows every step of the factorization process.

Factoring Calculator

Enter coefficients to factor a quadratic equation. The calculator will show step-by-step factorization using the AC method or appropriate technique.

Equation to Factor:

\[x^2 + 5x + 6 = 0\]

Factorization Result:

Factored Form: \[(x + 2)(x + 3) = 0\]
Solutions: \[x = -2, x = -3\]
Factorization Method: AC Method (Product-Sum)

Factorization Methods

AC Method

For quadratics in the form \(ax^2 + bx + c\) where \(a \neq 1\). Multiply \(a \times c\), find factors that sum to \(b\), then factor by grouping.

Example: \(6x^2 + 7x - 3\)

1. \(a \times c = 6 \times (-3) = -18\)

2. Find factors: \(9 \times (-2) = -18\), \(9 + (-2) = 7\)

3. Rewrite: \(6x^2 + 9x - 2x - 3\)

4. Group: \((6x^2 + 9x) + (-2x - 3)\)

5. Factor: \(3x(2x + 3) - 1(2x + 3)\)

6. Result: \((3x - 1)(2x + 3)\)

Simple Factoring

For quadratics where \(a = 1\). Find two numbers that multiply to \(c\) and add to \(b\).

Example: \(x^2 + 5x + 6\)

1. Find factors of 6: (1,6), (2,3), (-1,-6), (-2,-3)

2. Which pair sums to 5? 2 + 3 = 5 ✓

3. Result: \((x + 2)(x + 3)\)

Difference of Squares

For quadratics in the form \(a^2 - b^2 = (a - b)(a + b)\).

Example: \(x^2 - 9\)

1. Recognize pattern: \(x^2 - 3^2\)

2. Apply formula: \((x - 3)(x + 3)\)

Perfect Square Trinomial

For quadratics in the form \(a^2 \pm 2ab + b^2 = (a \pm b)^2\).

Example: \(x^2 + 6x + 9\)

1. Check: \(x^2 + 2(x)(3) + 3^2\)

2. Recognize: \((x + 3)^2\)

Worked Examples

Example 1: Simple Factoring

Factor \(x^2 - 5x + 6\)

Step 1: Find factors of 6 that sum to -5

Factors: (-2, -3) → -2 × -3 = 6, -2 + (-3) = -5 ✓

Step 2: Write factored form

\[(x - 2)(x - 3) = 0\]

Solutions: \(x = 2, x = 3\)

Example 2: AC Method

Factor \(2x^2 + 7x + 3\)

Step 1: \(a \times c = 2 \times 3 = 6\)

Step 2: Find factors of 6 that sum to 7

Factors: (1, 6) → 1 + 6 = 7 ✓

Step 3: Rewrite middle term

\[2x^2 + 1x + 6x + 3\]

Step 4: Factor by grouping

\[x(2x + 1) + 3(2x + 1)\]

Result: \[(x + 3)(2x + 1)\]

Example 3: Difference of Squares

Factor \(4x^2 - 25\)

Step 1: Recognize pattern

\[4x^2 - 25 = (2x)^2 - 5^2\]

Step 2: Apply formula \(a^2 - b^2 = (a - b)(a + b)\)

\[(2x - 5)(2x + 5)\]

Solutions: \(x = \frac{5}{2}, x = -\frac{5}{2}\)

Example 4: Perfect Square

Factor \(x^2 - 8x + 16\)

Step 1: Check if perfect square

\[x^2 - 2(x)(4) + 4^2\]

Step 2: Apply formula \((a - b)^2\)

\[(x - 4)^2\]

Solution: \(x = 4\) (double root)

Frequently Asked Questions

When should I use factoring instead of the quadratic formula? +

Factoring is fastest when the quadratic has integer coefficients and factors nicely. Use it when you can quickly find two numbers that multiply to \(ac\) and sum to \(b\). For complex coefficients or when factoring isn't obvious, use the quadratic formula.

What if the quadratic doesn't factor nicely? +

If a quadratic doesn't factor with integers, you have several options:

How do I factor quadratics with negative coefficients? +

The same methods apply! For negative \(c\), look for factors with opposite signs. For negative \(b\), look for factors that subtract to give the coefficient. Our calculator handles all sign combinations automatically.

Can all quadratics be factored? +

All quadratics can be factored over complex numbers, but not all factor nicely with integers or real numbers. Some quadratics require the quadratic formula or produce irrational/complex factors.

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