Determine the number of acres in a triangular parcel of land

Determine the number of acres in a triangular parcel of land if the lengths of the sides measure 1507 feet, 1750 and 970 feet. (Conversion: 43, 560 sq. ft.= 1 acre.) Number of Acres: ______ A 120-ft. pole is leaning. A 165-ft guy wire has been anchored 82 feet from the base of the pole.

Solution

42)

Use Heron\'s formula

A = (s (sa) (sb) (sc))

where a,b,c are side lengths, and
s = semi-perimeter = (a+b+c)/2

s = (1507+1750+970)/2 = 2113.5

A = (2113.5 (2113.51507) (2113.51750) (2113.5970))
A = (2113.5 (606.5) (363.5) (1143.5))
A = 729,939.42 ft²

A = 729,939.42 ft² / (43560 ft² / 1 acre) = 16.76 acres