Geometry heron's formula worksheet
Heron's formula needs only the three sides. Work out the semiperimeter s, half of the perimeter, then the area is the square root of s(s - a)(s - b)(s - c). No height and no angle.
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Sigma Prep · sigmaprep.io/worksheets Name Heron's FormulaDate Period Find the area of each triangle.
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Sigma Prep · sigmaprep.io/worksheets Name Heron's FormulaAnswer keyVersion 1Date Period Find the area of each triangle.
Free math worksheets at sigmaprep.io/worksheets© 2026 Sigma Prep |
How to do these
Sides and
- The semiperimeter is 42 / 2 = 21.
- Multiply 21 by 8, 7 and 6: that is 7056.
- The square root of 7056.
The answer is .
Where students go wrong
Using the whole perimeter instead of half of it. s is the semiperimeter, and with the full perimeter the product comes out sixteen times too big.
Also called s formula", or , .