find the area of a triangle whose vertices have coordinates:(5,5)(3,4)(8,3)

Answer 1

There are many ways to do this, you will have to tell me at what level of math this is.
e.g. Have you heard of Heron's Formula?
e.g. do you know the cosine law?

What grade level is this ?

Answer 2

I get 7/2

Answer 3

simplest way, list the points counterclock-wise, repeating the first point you started with
5 5
3 4
8 3
5 5

area = (1/2)(sum of down-products - sum of up-products)
= (1/2)(20+9+40 - (15+32+15))
= (1/2)(7)
= 7/2 , just as Steve had

btw, this method works for any convex polygon