Part (A):
The area of the penalty box.
The dimensions of the penalty box are (15x-1) and (5x-7)
The area of rectangle = length * width
∴ The area of the penalty box = (15x-1) * (5x-7) = 75 x² - 110 x + 7
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Part (B):
The area of the goal box.
The dimensions of the goal box are (7x-1) and (x+3)
The area of rectangle = length * width
∴ The area of the goal box = (7x-1) * (x+3) = 7x² + 20x - 3
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Part (C):
The area of the penalty box not coverd by the goal box =
The area of the penalty box - The area of the goal box =
(75 x² - 110 x + 7) - (7x² + 20x - 3) = 68 x² - 130 x + 10