Area of Triangle by Vertex Coordinates

A triangle PQR has vertices at points P(2, 1), Q(8, 5), and R(5, 11). Determine the area of triangle PQR using the formula for the area of a triangle given by vertices at coordinates (x1, y1), (x2, y2), (x3, y3):

$$ ext{Area} = rac{1}{2} imes |x_1(y_2 - y_3) + x_2(y_3 - y_1) + x_3(y_1 - y_2)| $$

If the vertices are P, Q, and R, which of the following is the area of triangle PQR?