4 sides different lengths area calculator

Calculation Method

For a quadrilateral with sides a, b, c, d and angle θ between a and d:

1. Split into two triangles using diagonal

2. Area of first triangle (sides a, d, θ): Area₁ = ½ × a × d × sin(θ)

3. For second triangle (sides b, c), we use Heron’s formula after calculating the diagonal length:

Diagonal length (p): p = √(a² + d² – 2×a×d×cos(θ))

Then for triangle with sides b, c, p: s = (b + c + p)/2

Area₂ = √(s×(s-b)×(s-c)×(s-p))

Total Area = Area₁ + Area₂