Carpentry & Building Construction © 2004

Area of a Triangle

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A triangle is a polygon with three sides and three angles. To find the area of a triangle, multiply its base times one-half its height. The formula for the area of a triangle is A = 1/2 bh.

Carpenters may calculate the area of triangles when they are estimating materials for gables or overhangs.

Practice Exercise

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Problem Exercises

1.		Find the area of a triangle whose base is 10' and height is 7'.
			A)	8.5 sq. ft.
			B)	35 sq. ft.
			C)	70 sq. ft.
			D)	140 sq. ft.
2.		Find the base of a triangle whose area is 48 sq. ft. and whose height is 8'.
			A)	96'
			B)	48'
			C)	24'
			D)	12'
3.		Find the approximate base of a gable that has an area of 45.5 sq. ft. and a height of 7'.
			A)	13'
			B)	26'
			C)	52.5'
			D)	65.5'
4.		The area for the side of an overhang with a 36'' base and a 22'' height is
			A)	33 sq. ft.
			B)	11 sq. ft.
			C)	5.50 sq. ft.
			D)	2.75 sq ft.
5.		An attic storage closet has a wall in the shape of a triangle. The area of the wall, whose base is 6' and whose height is 5' is
			A)	11 sq. ft.
			B)	15 sq. ft.
			C)	30.5 sq ft.
			D)	61 sq. ft.