Answer:
24 square units
Step-by-step explanation:
There are a couple of ways you can figure the area of the frame:
- subtract the inner area from the outer area
- multiply the width of the frame by the length of its centerline
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Subtract
The dimensions of the outer rectangle are twice the frame width plus the dimensions of the inner rectangle. That makes them 8 wide by 6 high. Then the difference of areas is ...
A = (8)(6) -(6)(4) = 48 -24 = 24 . . . . square units frame area
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Width by Length
The centerline of the frame is a rectangle with 1 unit greater length and width than the inner rectangle. It is 7 units by 5 units, so will have a perimeter of ...
P = 2(L+W) = 2(7+5) = 24 . . . . units
Then the area of the frame is this length multiplied by the width of the frame:
A = (24)(1) = 24 . . . . square units frame area
