How do you find the radius of a cylinder Given the surface area 289cm squared and height 21cm?

radius = diameter/2

radius = 6/2 = 3 inches

circumference = pi*diameter

circumference = 3.14*6 = 18.84 inches

area of circle = pi*(radius)^2

area of circle = 3.14*3^2 = 3.14*9 = 28.26 square inches

cylinder volume = (area of circle)*(height)

cylinder volume = 28.26*10 = 282.6 cubic inches

quadradic = 4

x^4 + 2x^3 + x - 1