Question

Find k, if the area of the triangle with vertices at A(k, 3), B(-5, 7), C(-1, 4) is 4 sq. units.

Answer 1

Answer:

Step-by-step explanation:formula for ar of triangle is 1/2(x1(y2-y3)+x2(y3-y1)+x3(y1-y2))=4sq

Answer 2

Answer:

k = 3

Step-by-step explanation:

Area of Triangle = (1/2)(x₁(y₂ - y₃) + x₂(y₃-y₁) + x₃(y₁ - y₂))

A =  x₁ = k   y₁= 3

B =  x₂ = -5   y₂=7

C =  x₃ = -1    y₃ = 4

=> Area of Triangle = (1/2) (k(7-4)  + (-5)(4-3) + (-1)(3 - 7))

=> Area of Triangle = (1/2) (3k  -5 + 4)

=> Area of Triangle = (1/2) (3k  -1)

Area of Triangle = 4 sq units

Equating both

(1/2) (3k  -1) = 4

=> 3k - 1 = 8

=> 3k = 9

=> k = 3