SOLUTION: A triangle has vertices (-2,1),(5,1),and(0,6)What is its area. Could someone explain to me how this is done. Thanks for your help.

Algebra ->  Triangles -> SOLUTION: A triangle has vertices (-2,1),(5,1),and(0,6)What is its area. Could someone explain to me how this is done. Thanks for your help.      Log On


   



Question 33995This question is from textbook prentice hall pre algebra
: A triangle has vertices (-2,1),(5,1),and(0,6)What is its area. Could someone explain to me how this is done. Thanks for your help. This question is from textbook prentice hall pre algebra

Found 2 solutions by mukhopadhyay, longjonsilver:
Answer by mukhopadhyay(490) About Me  (Show Source):
You can put this solution on YOUR website!
Using the vertices, calculate the length of each side of the traingle. You need to use the distance formula (using vertcies) to determine the length of each side. For example, if (a,b) and (c,d) are two vertices, the distance between them is Sqrt[(c-a)^2 + (d-b)^2]. After you find the length of each side, say, AB, BC, and CA are the sides, the area can be found out using the formula 1/2[(AB)(BC)+(BC)(CA)+(CA)(AB)] where AB = length of side AB etc.
Give it a try and send an email if you have any difficulty doing it.

Answer by longjonsilver(2297) About Me  (Show Source):
You can put this solution on YOUR website!
to find the area from 3 co-ordinates, you use something called the determinant, based upon matrix theory.

I am assuming you haven't done this, so i shall just quote the "formula" for you:



where the 3 coordinates are +%28x%5B1%5Dy%5B1%5D%29+, +%28x%5B2%5Dy%5B2%5D%29+ and +%28x%5B3%5Dy%5B3%5D%29+

jon.