Question

what was Newton's first law of motion?

Answer 1

when a body is in motion or rest it remains in the same rest unless there is an external force is applied.

Answer 2

$\textsf{Newton's\:First\:law\:of\:motion-}$

It states that if a body is at rest it remains to continue at rest if a body is at motion it remains to continue at motion until or unless external unbalanced force applied on it.

________________________________