CALCULUS
posted by Thomas on .
A triangle has verticies A(2.1,3), B(7,8,4), and C(5,0,2). Determine the area of triangle ABC.

This is actually a question from coordinate geometry. If (x1,y1), (x2,y2) and (x3,y3) are the vertices of a triangle then its area = (1/2))(x1(y2y3)+x2(y3y1)+x3(y1y2))
The coordinates of the vertices aren't very clear in your Q but assuming that the three points are (2.1,3),(7.8,4)& (5,0.2) the area of the triangle is 10.99 sq. units
Ajit