Factoring Trinomials Calculator

Factoring Trinomials Calculator

Factor a quadratic trinomial ax^2 + bx + c when it has rational roots, and see the discriminant and roots at the same time.

Last updated: June 2026 | By Patchworkr Team

Quadratic Factoring
Enter whole-number coefficients for a quadratic trinomial. The calculator factors only when the discriminant is a perfect square.
Result
Factored form
(x + 3)(x + 4)
Discriminant
1
Roots
x1 = -3 (-3.0000)
x2 = -4 (-4.0000)

What factoring means

Factoring rewrites a quadratic as a product of binomials. When the discriminant is a perfect square, the roots are rational and the trinomial factors cleanly.

When factoring fails

If the discriminant is negative, there are no real roots. If it is not a perfect square, the roots are irrational and the trinomial does not factor over the rationals.

Formula and example

ax^2 + bx + c

Example: 2x^2 + 5x + 3 = (2x + 3)(x + 1).

Worked Example

Factor 2x^2 + 5x + 3.

1. Compute the discriminant: 5^2 - 4 * 2 * 3 = 1.

2. Since 1 is a perfect square, the roots are rational.

3. The factors are (2x + 3)(x + 1).

Final answer: (2x + 3)(x + 1)

Frequently Asked Questions

What if the trinomial is not factorable?

The calculator explains that the discriminant is not a perfect square, so the polynomial does not factor over the rationals.

Why require whole numbers?

The tool is designed for exact factoring of standard quadratics with integer coefficients.

What does the discriminant tell me?

It tells you how many real roots the quadratic has and whether the roots are rational or irrational.

What if a = 0?

Then the expression is not quadratic, so it is rejected as an invalid trinomial input.

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