Problem Solving (PS) | Re: In the figure above, if AC = 18, what is the area of ∆ BCD?

Since triangle ABD is a right triangle, we see that it’s a 6-8-10 right triangle with a height of 6. Thus, the area of triangle ABD is (8 x 6)/2 = 24.

Since triangle ABC is also a right triangle, the area of triangle ABC is[18 x 6] /2 = 54.

Since the area of triangle BCD is the difference between the areas
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