Question

The area of the triangle with vertices at (-4,-1), (1,2),(4,3) is


a) 12

b) 18

c) 17

d) 30


​

Answer 1

Given :

• Coordinates of A = ( - 4 , - 1 )

• Coordinates of B = ( 1 , 2 )

• Coordinates of C = ( 4 , 3 )

To Find :

• Area of triangle made by joining of given vertices

Solution :

→ Area = 1/2 [ x₁ ( y₂ - y₃ ) + x₂ ( y₃ - y₁ ) + x₃ ( y₁ - y₂ ) ]

Here

x₁ = - 4 x₂ = 1 x₃ = 4

y₁ = - 1 y₂ = 2 y₃ = 3

Substitute values in formula

⇒ 1/2 [ - 4 ( 2 - 3 ) + 1 ( 3 + 1 ) + 4 ( - 1 - 2 ) ]

⇒ 1/2 [ 4 + 4 - 12 ]

⇒ 1/2 [ - 4 ]

⇒ - 2

All options are wrong