Final answer:
The magnitude of vector X is 12 units.
Step-by-step explanation:
To find the magnitude of the vector X, we can use the Pythagorean theorem. Since the resultant vector lies along the positive x-axis and has the same magnitude as X, we know that the resultant vector has no y-component. This means that the y-component of vector Y = 12i - 16j is cancelled out by the vector X.
Therefore, the magnitude of X can be found by taking the square root of the x-component of Y squared:
Magnitude of X = √(12^2) = 12 units.