Question

Find the values of 'K' if area of triangle is 4 square units and vertices are (k, 0), (4, 0), (0, 2).

Options

• (–2, 0)

• (0, 4)

• (0, 8)

• (–2, 4)

Answer 1

(0, 8)

Explanation:

The relation gives the area of the triangle with vertices (k, 0), (4, 0), and (0, 2).

Δ = `1/2 |(k, 0, 1),(4, 0, 1),(0, 2, 1)|`

= `1/2 [k(0 - 2) - 0(4 - 0) + 1(8 - 0)]`

= `1/2[-2k + 8] = k + 4`

∴ `- k + 4 = +- 4` 

When `- k + 4 = - 4, k = 8`

When `- k + 4 = - 4, k = 0`

Therefore k = 0, 8