The area of the room is
square feet so Michelle's reasoning was incorrect.
Explanation:
Step 1:
To calculate the area of the given room, we divide the unknown shape into known shapes.
The room's shape is made of 2 rectangles.
The area of a rectangle is the product of its length and its width.
One rectangle has a length of 10 feet and a width of
feet.
The other rectangle has a length of
feet and a width of
feet.
Step 2:
The area of the first rectangle
square feet.
The area of the second rectangle
square feet.
The total area of the room
square feet.
The area of the room is
square feet so Michelle's reasoning was incorrect.