Basic formulas for area calculations.
For estimating quantity needed for irregular areas break the area up into smaller workable shapes. Measure each of them and assign them a letter. Calculate square feet for each and add the square footage together to figure total needed.
Rectangle area = length x width
Circle area = Pi x Radius Squared
Triangle area = (length x width) / 2
Ellipse area = ½ length x ½ width x Pi
Parabola area = ⅔ side x height
Pi = 3.1416