As shown in the figure above, the coordinates of the four vertices of the quadrilateral ABCD are a (- 2,0), B (1,7) and C (5,5) As shown in the figure above, the coordinates of the four vertices of the quadrilateral ABCD are a (- 2,0), B (1,7), C (5,5) D (7,0) tries to find the area of this quadrilateral; As shown in the figure above, the coordinates of the four vertices of the quadrilateral ABCD are a (- 2,0), B (1,7), C (5,5) D (7,0) try to find the area of this quadrilateral;

As shown in the figure above, the coordinates of the four vertices of the quadrilateral ABCD are a (- 2,0), B (1,7) and C (5,5) As shown in the figure above, the coordinates of the four vertices of the quadrilateral ABCD are a (- 2,0), B (1,7), C (5,5) D (7,0) tries to find the area of this quadrilateral; As shown in the figure above, the coordinates of the four vertices of the quadrilateral ABCD are a (- 2,0), B (1,7), C (5,5) D (7,0) try to find the area of this quadrilateral;

-2(7)+1(5)+5(0)+7(0)-0(1)-7(5)-5(7)-0(-2)/2=-79/2
=39.5unit