STANDARD HANDBOOK OF PETROLEUM & NATURAL GAS ...

Geometry 9
area = bh = ab sin c = 1/2
D,D, sin u
where u = angle between diagonals D, and D,
Trapezoid (Figure 1-7)
area = 1/2 (a + b)h'= 1/2 D,D, sin u
where u = angle between diagonals D, and D,
and where bases a and b are parallel.
Any quadrilateral (Figure 1-8)
area = 1/2
D,D, sin u
Note: a2 + b2 + c2 + d*= D2 + D* + 4m*
1 2
where m = distance between midpoints of D, and D,
Circles
area = nr2 = 1/2 Cr = 1/4 Cd = 1/4 nd2 = 0.785398d2
where r = radius
d = diameter
C = circumference = 2nr = nd