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Question
Find the area of a triangle with vertices at the point given in the following:
(1, 0), (6, 0), (4, 3)
Solution
Area of the triangle passing through the vertices `(x_1,y_1),(x_2,y_2),(x_3,y_3)`
`Delta = 1/2 abs ((x_1,y_1,1),(x_2,y_2,1),(x_3,y_3,1))`
Area of the required triangle
`Delta = 1/2 abs((1,0,1),(6,0,1),(4,3,1))`
`=1/2 [1 (0 - 3) - 0 (6 - 4) + 1 (18 - 0)] `
`= 1/2 [-3 + 18]`
`= 15/2`
= 7.5 sq. units.
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