What is the formula for finding the area of a regular polygon work perimeter p and apothem length a?

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Acircle has a circumference of 28.36 units what is the diameter of the circle

4. (10.03 mc) the equation of line cd is y = −2x − 2. write an equation of a line parallel to line cd in slope-intercept form that contains point (4, 5). (4 points) y = −2x + 13 y = negative 1 over 2 x + 7 y = negative 1 over 2 x + 3 − 2x − 3