if i assign 4 position(x,y) can i make a point and line to connect it together like freehand drawing

if i assign 4 position(x,y) can i make a point and line to connect it together like freehand drawing ? and i can find the area of this ?

Answer 1

[Walter Roberson]

X = [x1 x2 x3 x4 x1];
Y = [y1 y2 y3 y4 y1];
plot(X,Y)
polyarea(X,Y)