Ex. 3. Required the area of a triangle, whofe base is 12 feet 3 inches, and perpendicular 8 feet 9 inches. Anf. 53 feet 7 in. 1 pt. 6". Ex. 4. How many fquare yards are contained in a triangular garden, the length of one of its fides being 80 yards, and the perpendicular distance between that fide and the oppofite angle 70 yards? Anf. 2800 fquare yards. Ex. 5. What is the expence of paving a triangular court, at 4s. 6d. per fquare yard, one of its fides being 48 feet 6 inches, and perpendicular 30 feet? Anf. 181. 9s. 94d. PROBLEM VI. Plate 6. fig. 74. One of the angles of a triangle and the containing fides being given, to find the area. RULE I. As radius, is to the fine of the included angle, fo is half. the product of the containing fides, to the area. RULE 2. Find the perpendicular by trigonometry, and proceed as in the preceding problem. EXAMPLE I. Required the area of a triangle, whose included angle is 63° 30', and the containing fides 806 and 70c links of the English chain. 2.52479 = 2 acres 2 roods, 4 per. nearly. Ex. 2. How many fquare yards are in a triangle, whofe fides are 100.98, feet, and included angle 45° ? Anf. 384 fq. yds 8 or 8.8 feet. Ex. 3. Required the area of a triangle, when the containing fides are 409 and 220 yards, and the included angle 30% Anf. 22495 fq. yds. Ex. 4 Required the area of a triangular field ABC, AB= 6000, AC 8000 links of the Scots chain, and angle A 39° 36′. Anf. 153 acres. Ex. 5. Required the area of a triangle, the containing fides being 214 and 25 yards, and the contamed angle 50°. Anf. 203 yards. PROBLEM VII. Plate 6. fig. 75. The three fides of any triangle being given, to find the area. RULE. Add the three given fides, and from half their sum subtra& the fides feverally: Multiply the half fum and the three re mainders |