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Do men from Mars have green skin and antennae? When given the equations x-y=-1, 2y-x=27, x+y =11 how would you use row echelon form to get to the answer (5,6)? Find the average rate of change for the function.? Math help please? I cant find the equation for this graph? Surface by rotating the arc y^2=9x from x=0 to 4 through 2π around x axis is 49π.Show that
x̄ of this surface is: 3/49*integral{x(4x+9)dx}?