Worked example
Operation: Square a: 3 Unit: m
→ 12 m
Method and scope
a is the radius for a circle; otherwise a,b,c,d are side lengths and h is perpendicular height. Triangles use all three sides for both area and perimeter and must satisfy the triangle inequality. Trapezoids use parallel bases a,b; area uses h, perimeter uses legs c,d.
4a; 2(a+b); 2πa; a+b+c; 2(a+b); a+b+c+d
Precision and limits
≈ marks an approximation. Display rounding does not change the internal calculation.