Question

is inertia the opposite of motion? no, inertia is a property of all matter whether the matter is moving or not yes

Explanation:

Inertia is a property of matter that resists changes in motion. It is not the opposite of motion but rather a characteristic that affects how an object responds to forces. Matter can have inertia whether it is at rest or in motion. For example, a bowling ball at rest (like the one in the image) has inertia that resists being set in motion, and once in motion, it has inertia that resists stopping.

Answer:

no, inertia is a property of all matter whether the matter is moving or not