question_answer

Area of quadrilateral formed by the vertices \[(-1,6),\,(-3,-9),\,(5,-8)\] and (3, 9) is _____ (sq. units).

A)  96      

B)         18                  

C)  50      

D)         25

Correct Answer: A

Solution :

Let \[A(-1,6),\,B(-3,-9),\,C(5,-8)\] and \[D(3,9)\]are the vertices of quadrilateral ABCD. Then, Area of quadrilateral ABCD = Area of \[\Delta \,ABC\]Area of \[\Delta \,ACD\]       .... (i) Area of (ABCD) \[=59+37=96\]sq. units.