Use the formula: Area = 1/2 × base × height
Measure the base of the triangle
Measure the perpendicular height from the base to the opposite vertex
Multiply the base by the height
Divide the result by 2
The result is the square footage of the triangle if the measurements are in feet
If the measurements are in inches, convert to feet before calculating
For a triangle with sides only, use Heron’s formula: Area = sqrt[s(s-a)(s-b)(s-c)]
In Heron’s formula, s = (a + b + c) / 2
Convert the final area to square feet if needed