How to use this calculator
- Identify the measurements labelled Base a, Base b, Height h. Check whether the figure satisfies the assumptions described below.
- Enter positive measurements in a common unit. Use the degree symbol convention for angles. Ratios such as eccentricity have no unit.
- Select Calculate. Inspect the result labels: lengths, areas and volumes have different dimensions. Copy the output or print the page if you need a record.
The formula
Base a = 10; Base b = 6; Height h = 4
Worked example
For Base a = 10 cm, Base b = 6 cm, Height h = 4 cm, applying the displayed relationship gives area ≈ 32 cm². The remaining related measurements appear in the result panel. The example uses ideal dimensions and rounds only for display.
Model and limitations
Its height is the perpendicular separation of the bases. The midline joins the midpoints of the legs and has length (a+b)/2. Multiplying this midline by the height gives the area.
Equal bases with arbitrary legs do not uniquely determine a height. The four-side tool rejects that ambiguous case. Inputs are limited to 10⁹ for lengths, 10¹⁸ for areas and 10²⁷ for volumes. Extremely thin or nearly degenerate figures may lose numerical accuracy; avoid treating displayed rounding as a measurement tolerance.