(i) (2, 3), (-1, 0), (2, -4)<br> (ii) (-5, -1), (3, -5), (5, 2)
Solution:
The formula for calculating the area of a triangle is = 1/2 × [x1(y2 – y3) + x2(y3 – y1) + x3(y1 – y2)]
(i) Given here,
x1 = 2, x2 = -1, x3 = 2, y1 = 3, y2 = 0 and y3 = -4
If we substitute all of the values in the formula above, we get
The area of triangle = 1/2 [2 {0- (-4)} + (-1) {(-4) – (3)} + 2 (3 – 0)]
= 1/2 {8 + 7 + 6}
= 21/2
As a result, the triangles’ area is 21/2 square units.
(ii) Given here,
x1 = -5, x2 = 3, x3 = 5, y1 = -1, y2 = -5 and y3 = 2
The area of the triangle = 1/2 [-5 { (-5)- (2)} + 3(2-(-1)) + 5{-1 – (-5)}]
= 1/2{35 + 9 + 20} = 32
As a result, the triangles’ area is 32 square units.