Answer:
65.
Explanation:
1) the required area is (all the details are in the attachment):
A=Area-area₁-area₂, where Area is the area of the square ABDG; area₁ is the area of the triangle FGH; area₂ is the area of the triangle CDE;
2) Area=AB²=81; area₁=0.5*4*3=6; area₂=0.5*5*4=10;
3) finally, A=81-6-10=65 [units²].