| Form |
 |
Method of Finding Areas |
| Triangle |
|
 |
|
Base x 1/2 perpendicular height
s = 1/2 sum of the three sides a, b, c |
|
| Trapezium |
|
 |
|
| Sum of area of the two triangles |
|
| Trapezoid |
|
 |
|
| 1/2 sum of parallel sides x perpendicular height |
|
| Parallelogram |
|
 |
|
| Base x perpendicular height |
|
| Regular Polygon |
|
 |
|
| 1/2 sum of sides x inside radius |
|
| Circle |
|
 |
|
| 0.7854 x diameter2 = 0.07958 x circumference2 |
|
| Sector of a Circle |
|
 |
|
 = 0.0087266 r2Ao= arc x 1/2 radius |
|
| Segment of a Circle |
|
 |
|
|
Circle
of same area as a square |
|
 |
|
| Diameter = side x 1.12838 |
|
Square
of same area as circle |
|
 |
|
| Side = diameter x 0.88623 |
|
| Ellipse |
|
 |
|
| Long diameter x short diameter x 0.78540 |
|
| Parabola |
|
 |
|
| Base x 2/3 perpendicular height |
|
