Brahmagupta’s formula
Solve brahmagupta’s formula with your values and follow each calculation step.
Inputs
Use the units shown—
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Formula & explanation
A = √[(s−a)(s−b)(s−c)(s−d)], s=(a+b+c+d)/2
Variables & units
- Side a
- cm · minimum 0, maximum 1000000
- Side b
- cm · minimum 0, maximum 1000000
- Side c
- cm · minimum 0, maximum 1000000
- Side d
- cm · minimum 0, maximum 1000000
Worked example
A cyclic quadrilateral with consecutive sides 3,4,3,4 cm has area 12 cm².
Assumptions
This formula requires a cyclic quadrilateral. Side lengths alone do not verify that your drawn quadrilateral is cyclic.
Formula version 1.0.0. JavaScript floating-point arithmetic applies. Results display up to 6 decimal places; stored values retain available precision. Use the units shown.
Practice with an example
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