[QUOTE=viet;98972][quote]Let T be the triangle with vertices at (4,10), (−8,8),(3,8). The area of T is = ?You can get the area of the triangle directly using Heron's formula.

i used the projection forumla and got the length of 1 side as: 4.2426 (not sure if that is right). should i do the same thing to find the other sides?

-Dan