Question

Find the area of the triangle with the given measurements. Round the solution to the nearest hundredth if necessary. A = 46°, b = 27 ft, c = 14 ft

Answer 1

We will use the law of cosines
side a² = b² + c² -2bc • cos(A)
side a² = 729 + 196 -2*27*14 * cos (46)
side a² = 925 -(756 * 0.69466)
side a² = 399.83704
side a = 19.995925585
We could round that to 20
a = 20 b = 27 c =14

We can calculate a triangle's area when we know all 3 sides by using Heron's Formula
area = square root (s • (s - a) • (s - b) • (s - c))

where s is the semi-perimeter
semi-perimeter = (side a + side b + side c) ÷ 2
s = (20 + 27 + 14) / 2
s = 30.5
Now we use Heron's Formula
area = square root (s • (s - a) • (s - b) • (s - c))
area = square root (30.5 • (30.5 - 20) • (30.5 - 27) • (30.5 - 14))
area = square root (30.5 • (10.5) • (3.5) • (16.5))
area = square root (18494.4375)
area = 135.9942553934  which rounds to
136 square feet
Source:
http://www.1728.org/triang.htm