To compute the square feet area of a SQUARE or
RECTANGLE (fig. 15-18), use the following
equation:
Area = Base x Height or (A = B x H).
Since a RIGHT TRIANGLE is a square or
rectangle cut in half diagonally, the same equation can
be used to compute the area and the result divided by
2 (fig. 15-19). For example,
Another geometric figure you may encounter in a
cross section is a TRAPEZOID (fig. 15-20). The
equation to compute the area of a trapezoid is as
follows:
The next step is to compute the total area in the
cross section (fig. 15-21). This is accomplished by
adding the results of each geometric figure in the cross
Figure 15-18.—Area of a square and rectangle.
Figure 15-19.—Area of a triangle.
15-14
