Anna has a total of 36 goldfish in her aquarium, some are orange and some are black. The number of orange goldfish is 7 more than twice the number of black goldfish. Which system of equations below can be used to describe the number of black and orange goldfish in Anna's aquarium?(Let x represent the number of orange goldfish and y represent the number of black goldfish.)A. x + y = 36x - 2y = 7B. x - y = 7x + 2y = 36C. x - y = 36x + 2y = 7D. x + y = 7x - 2y = 36