For this, we need to find the area of the larger rectangle (The room) and subtract from that the area of the smaller, shaded rectangle (The rug). A=LW (L=Length, W=Width, A=Area)
The larger rectangle first: A=(15)(10) A=150 feet squared
Now the Rug: A=(12)(7) A=84 feet squared
Now to find the area that is NOT covered by the rug, we subtract: 150-84 = 66 feet squared will NOT be covered by the rug.
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