King High School has asked Franklin to paint some murals around the school, and Franklin is thrilled! His mural in the main office will show a ray of sunlight breaking through storm clouds. Franklin creates the perfect gray for storm clouds. There is a proportional relationship between the number of cans of black paint, x, and the number of cans of white paint, y, Franklin mixes together. The equation that models this relationship is y=2x.
How much black paint would Franklin mix with 8 cans of white paint to create storm clouds? Write your answer as a whole number or decimal.