Find the area of triangle ABC if AB = BC = 12 and angle ABC = 120 degrees.

If no ones too busy making out today I sure would love some help on this problem!

AnonymousConfusedGuy Feb 14, 2018

#1**+3 **

Area=1/2absinC

Area=1/2*12*12*sin120

Area=1/2*144*sin120

Area=72*sin120

Area=62.4cmÂ²(1dp)

qualitystreet Feb 14, 2018

#2**+2 **

sin 30 = h/12 h= 6

6^2 + (1/2b)^2) = 12^2

(1/2 b)^2 = 144-36 = 108

b=20.78

Area = 1/2 bh = 1/2 20.78 x 6 = 62.35 units^2

ElectricPavlov Feb 14, 2018