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Question
Find the area of a triangle whose vertices are
(a, c + a), (a, c) and (−a, c − a)
Solution
We know area of triangle formed by three points (x1y1) , (x2y2), and (x3y3)is given by `triangle=1/2 [x_1(y_2-y_3)+x_2(y_3-y_1)+x_3(y_1-y_2)]`
The vertices are given as (a, c + a), (a, c) and (−a, c − a)
Δ = 1/2[a (c-c+a) + a(c-a-c-a)-a(c+a-c)
= 1/2[a(a)+a(2a)-a(a)]
= 1/2 [-2a2]=a2
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