To find the area of a triangle given the coordinates of its vertices, we use the formula derived from the determinant method:
Area = $\frac{1}{2} |x_1(y_2 - y_3) + x_2(y_3 - y_1) + x_3(y_1 - y_2)|$
Let the vertices be:
Substitute the coordinate values into the area formula:
Area = $\frac{1}{2} |2((-1) - 3) + (-3)(3 - 4) + 5(4 - (-1))|$
Calculate the terms inside the absolute value:
Now sum these values:
Area = $\frac{1}{2} |-8 + 3 + 25|$
Area = $\frac{1}{2} |-5 + 25|$
Area = $\frac{1}{2} |20|$
Area = $\frac{1}{2} \times 20$
The calculated area is:
Area = $10$ square units.
Find the co-ordinates of the centroid of a triangle whose vertices are A(1, 4), B(7, 8) and C(10, 12).