This is to do with mechanics, which as far as I know is pre-calc, not pre-algebra.

Question: A particle has an initial velocity of $\displaystyle i+2j$ and is accelerating in the direction $\displaystyle i+j$. If the magnitude of the acceleration is $\displaystyle 5\sqrt{2}$, find the velocity vector and the speed of the particle after 2 seconds.

Answer:

velocity vector: $\displaystyle 11i+12j$

speed of particle: $\displaystyle \sqrt{265} ms^{-1}$

I am literally stumped on how to achieve this answer. If you can tell me what to do to get there, I will try working it out .