A triangle has two corners with angles of # pi / 2 # and # (3 pi )/ 8 #. If one side of the triangle has a length of #12 #, what is the largest possible area of the triangle?

1 Answer
Jan 9, 2018

Largest possible Area of Delta ABC = #A_t = color (red)(173.8236)#

Explanation:

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#C = pi / 2, B = (3pi)/8, A = pi - pi/2 - (3pi)/8 = pi / 8#

Side 12 should correspond to the smallest angle (pi/8) to get the largest possible area.

#12 / sin (pi/8) = b / sin ((3pi) / 8) = c / sin (pi/2)#

#b = (12 * sin ((3pi)/8)) / sin (pi/8) = 28.9706#

#c = (12sin(pi/2)) / sin (pi/8) = 31.3575#

Largest possible area of Delta ABC = #A_t = (1/2) b a = (1/2) * 28.9706 * 12 = color (red)(173.8236)#