Area of a rectangle=length x width
You have two rectangles:
First rectangle (the biggest):
length=9 yd
width=12 yd-6 yd=6 yd
Area of the biggest rectangle=(9 yd)(6 yd)=54 yd²
Second rectangle (the smallest)
length=6 yd
width=3 yd
Area of the smallest rectangle=(6 yd)(3 yd)=18 yd²
Area of the ballroom=area of the biggest rectangle + area of the smallest rectangle.
area of the ballroom=54 yd² +18 yd²=72 yd²
