Then e (- 1 1, 0)
So CE = |-14-(-11) | = 3.
BE=|6-0|=6
So the right triangle BEC area =6*3/2=9.
Auto-focus by the direction perpendicular to the X-axis.
Then f (-2,0)
So FD=|-2-0|=2.
AF=|8-0|=8
So the right triangle AFD area =2*8/2=8.
BEFA is a right-angled trapezoid
High EF=|- 1 1-(-2)|=9.
BE=6,AF=8
So the area =(6+8)*9/2=63.
So ABCD area =9+8+63=80.
The abscissa of each vertex of ABCD remains unchanged, and the ordinate increases by 2.
Translate the quadrilateral up by two units,
That is, it is still the original quadrangle, so the area remains the same, or 80.