SOLUTION: find the area of the traingle using determinants (-1,3) (-2,0) (4,1)

Algebra ->  Matrices-and-determiminant -> SOLUTION: find the area of the traingle using determinants (-1,3) (-2,0) (4,1)      Log On


   

Question 368137: find the area of the traingle using determinants
(-1,3) (-2,0) (4,1)
Answer by Edwin McCravy(20086) About Me  (Show Source):
You can put this solution on YOUR website!
The determinant formula:
The area of the triangle whose vertices are (x1,y1),(x2,y2), (x3,y3)
is given by this formula:



You can put the points in in any order as long as you take the absolute value
of the determinant:
(-1,3) (-2,0) (4,1)
Area=expr%281%2F2%29abs%28%28matrix%283%2C3%2C-1%2C3%2C1%2C-2%2C0%2C1%2C4%2C1%2C1%29%29%29

Do you know how to expand (i.e., evaluate) a determinant? If not post again,
asking how. The value of the determinant is 17 so

Area=expr%281%2F2%29%2Aabs%2817%29+=+17%2F2=8%261%2F2

Edwin