Question

The earth-moon relationship is unique in many ways. It is the largest moon in the solar system relative to its host planet. The relative size between the earth and moon are so close, some refer to it as a ________ planet system.

Answer 1

The answer is a BINARY planet system:)
Hope I could help, have a great one

Answer 2

Double/Binary

Step-by-step explanation:

The Moon is the only natural satellite of the Earth. Moon is fifth largest natural satellite of a planet in the Solar system. It is only satellite which is very close to the planet and large. Moon is about one-fourth the size of the Earth. For this reason, the moon-Earth system is referred as binary or double planet system.