how ı can calculate area and volume ıf have 4 Coordinates like (x1,y1) (x2,y2) (x3,y3) (x4,y4)

(2,4) (7,5) (4,6) (3,8)

area=?

volume=?

[Walter Roberson]

A tetrahedron?

Answer 1

[Roger Stafford]

Abdul, I will modify your question a little, since the volume of 2D objects is always zero. Instead let it be this: Calculate the volume and surface area of a tetrahedron whose four vertices are the four 3D points: P1 = [x1;y1;z1], P2 = [x2;y2;z2], P3 = [x3;y3;z3], P4 = [x4;y4;z4].

   Volume = 1/6*abs(dot(cross(P2-P1,P3-P1),P4-P1));
   Area123 = 1/2*norm(cross(P2-P1,P3-P1)); % Area of triangle P1P2P3

The areas of the other three triangles are calculated using easy modifications of the formula for Area123.

Answer 2

[Walter Roberson]

Volume of a planar figure does not make any sense.

If you had 3 dimensional coordinates then see http://www.had2know.com/academics/tetrahedron-volume-4-vertices.html