What is the length of a ray whose x-component is -2 units long and whose y-component is -4 units long

You can find the length of the ray using Pythagorean's theorem. This theorem relates the three sides of a right triangle. The length of the ray is the hypotenuse, while the other two legs are the x and y components. The solution is as follows:

L = √(x² + y²)
L = √((-2)² + (-4)²)
L = 4.47 units

More information

That depends on what kind of environ meant it is in  in space it has the same force that was applied when the velocity was gained