Find the area of the triangle defined by the coordinates (7, 1), (0, 10), and (9, 4). (To the nearest tenth)

A) 12.5 square units

B) 17.5 square units

C) 19.5 square units

D) 22.5 square units

The sides of the triangle is known however its height is not. We need to use Heron's formula to solve for the area of the triangle.

a = 3.32; b = 11.40; c = 10.82

Find variable s; 1/2 of the perimeter of the triangle

s = (3.32 + 11.40 + 10.82) / 2 = 12.77

Area = sqr (s (s-a) (s-b) (s-c).

A = √12.77 (12.77-3.32) (12.77-11.40) (12.77-10.82)

A = √12.77 (9.45) (1.37) (1.95)

A = √322.39

A = 17.96

The closest figure is 17.50 square units