Find volume and where to draw a line to separate a and b

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The equation x2 – 1x – 90 = 0 has solutions {a, b}. what is a + b?

Asquare has a side that measures 11 units. what is the area of a circle with a circumference that equals the perimeter of the square? use 3.14 for π, and round your answer to the nearest hundredth. 1519.76 units2 379.94 units2 616.56 units2 154.14 units2