math calculator

Quadratic Formula Calculator

Solve any quadratic equation ax² + bx + c = 0 instantly and get both real roots (if they exist). Perfect for algebra homework, physics projectile motion or graphing parabolas.

Important Use Notice

Informational calculator only. Verify important outputs independently before legal, tax, medical, engineering, safety-critical, contractual, employment, or compliance use.

Estimate

Enter job values, review the estimate, then use the decision hints before ordering or quoting.

Estimate Results

Enter values to see the result.

Example

x² - 5x + 6 = 0 → roots: 2 and 3

Formula

x = [-b ± √(b² - 4ac)] / (2a)

The discriminant (b² - 4ac) determines the number of roots. If D > 0 — two real roots, D = 0 — one repeated root, D < 0 — no real roots.

Vertex form: y = a(x - h)² + k where h = -b/(2a)

Check

Forgetting the ± in the formula
Confirm that all inputs use the same unit system expected by the formula.

Next Step

FAQ

What if discriminant is negative?

No real roots — the equation has complex conjugate roots (e. g. , 1+2i, 1-2i). This basic calculator shows "No real roots".

Why do quadratic equations have two roots?

Parabolas can cross the x-axis at two points, one point, or not at all, depending on the discriminant.