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2 Find the lateral (side) surface area of the cone generated by revolving the line segment y = - x, 0=x = 7, about the x-axis. Check your answer with the following geometry formula. Lateral surface area = - x base circumference x slant height N Set up the integral that gives the surface area of the cone S= (Type exact answers, using it as needed.) The lateral surface area is (Type an exact answer, using it as needed.)