Parabola Properties Calculator (vertex x = −b/2a)

The calculator applies the exact formula vertex (−b/2a, c − b²/4a), focus, directrix. Worked example: y = x² − 4x + 3 → vertex (2, −1), focus (2, −0.75). Keep every input in one unit system and the result follows in the same coordinate units; full precision is kept until the final rounding.

1. 1

   Enter the measurements

   Type the values required by the formula for parabola properties.

2. 2

   Check the units

   One unit system throughout — cm, m, ft or in.

3. 3

   Read the result

   The calculator substitutes, evaluates and rounds only at the end.

• 1

  Distance is symmetric: d(A,B) = d(B,A)

• 2

  Squaring removes sign worries on differences

• 3

  Plot the points to catch swapped coordinates

• Swapping x and y in one point

• Mixing 2D and 3D coordinate triples

• Forgetting the square root before the final answer