In a triangle ABC, side BC = 8.1 cm, side AC = 7 cm, and angle ACB = 30 degrees. What is the area of the triangle?
Initially, one might think to use area = 1/2 x base x height, however drawing the triangle immediately shows that this is not possible here. We then think to use the formula for area using two adjacent sides and the angle inbetween. Looking at our triangle we realise that it is of the correct form. The formula we need to use is = 1/2absinC.In this case, a = 8.1, b = 7, C = 30 degrees, and inputting this into the formula, using that sin30 = 1/2, we get: area = 1/2x8.1x7x1/2 = 14.175.
EB
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