A statement that's known to be always true or always false is a

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An arc subtends a central angle measuring 7pi/4 radians what fraction of the circumference is this arc?

The area of a rectangle is 10 cm^2. one side of the rectangle is x cm. express the perimeter of the rectangle in terms of x and show that this rectangle cannot have a perimeter of 12 cm. the perimeter of the rectangle in terms of x is __ cm