Say I have function $y -2 = -4(x + 1)$. Is it a valid use of $\Rightarrow$ to, in the course of simplification, do this:
$y -2 = -4(x + 1) \Rightarrow y = -4x -2$?
Both sides of the equation are equal, and from what I understand of that symbol this is appropriate, but I'm not sure.
For all of high school I did something similar to this, except I just used $\rightarrow$ between the steps, especially in Algebra, to keep the actual simplifications separate, and never had any issues with any teachers doing this. I felt it kept my work cleaner, but my Calc professor marks us down for doing that, and I'd prefer to be able to separate steps out a bit more than
$y -2 = -4(x + 1) = y = -4x -2$