Find the area if the triangle whose side have lengths of 101

Find the area if the triangle whose side have lengths of 10.11, and 12 feet. 51.5 sq. feet 22 sq. feet 66 sq. feet 592 sq. feet If A = (1, Squareroot 3) and B = (-1, -Squareroot 3), find the direction angle for 2A + B. 60 degree 0 degree 30 degree 90 degree

Solution

1) semiperimeter = s = (10+11+12)/2 = 16.5

using heron\'s formula area = sqrt[s*(s-a)*(s-b)*(s-c)] =n sqrt [16.5 * 6.5 * 5.5 * 4.5] = 51.52 sq. feet

2) 2A + B = < 2-1, 2sqrt(3) - sqrt(3) > = <1,sqrt(3)>

tan(theta) = sqrt(3)/1 => theta = 60 degree from x-axis in anticlockwise direction