Find values of k if area of triangle is 4 sq. units and vertices are
(i) `(k, 0), (4, 0), (0, 2)`
(ii) `(–2, 0), (0, 4), (0, k)`

Explanation

Area of a triangle is given by,

`Ar = 1/2|[x_1,y_1,1],[x_2,y_2,1],[x_3,y_3,1]|`

So, putting the given vertices,

`Ar = 1/2|[-2,0,1],[0,4,1],[0,k,1]|`

As Area is `4` square units,

`So, 1/2|[-2,0,1],[0,4,1],[0,k,1]| = 4`

`=>|[-2,0,1],[0,4,1],[0,k,1]| = 8`

`=>-2(4-k)-0+1(0,0) = +-8`

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