What must be different for a system to have one solution

Find the vertex of the function given below y=x^2-6x+1

Three cylinders have a height of 8 cm. cylinder 1 has a radius of 1 cm. cylinder 2 has a radius of 2 cm. cylinder 3 has a radius of 3 cm. find the volume of each cylinder ( ! : ”0 )

James was playing a game with his friends. he won 35 points. then he lost 15, lost 40 and won 55. how did he come out