Suppose that two objects form together (i. e., at the same time), in orbit around each other, one with a mass 15 times that of Jupiter, and the other 5 times that of Jupiter. Would these objects be classified as planets

The two objects will not be classified as planets

Explanation:

Planets are formed through a method known as accretion. This is an accepted method of planets formation, which explains that planet began as dust grains in orbit around the central protostar.

Thus, two objects whose masses are far greater than mass of Jupiter cannot be classified as planet because the process of the planet formation is not in line with the acceptable method.