Two corners of a triangle have angles of (5 pi )/ 8 5π8 and ( pi ) / 3 π3. If one side of the triangle has a length of 12 12, what is the longest possible perimeter of the triangle?

1 Answer
Oct 18, 2017

Longest possible perimeter = 142.9052=142.9052

Explanation:

Three angles are pi/3, (5pi )/ 8, (pi - (pi/3+(5pi)/8)π3,5π8,(π(π3+5π8)
=pi/3, (5pi)/8, pi/24)π3,5π8,π24)

To get longest possible perimeter, length 12 should correspond to least angle pi/24π24
:. 12/sin (pi/24) = b / sin ((5pi)/8) = c / sin (pi/3)

c = (12* sin(pi/3)) / sin (pi/24) = 45.9678
b = (12 * (sin (5pi)/8))/sin (pi/24) = 84.9374

Perimeter = 12 + 45.9678 + 84.9374 = 142.9052