OK, so we're cool with the easy notation like
These ( ) are killer important!
What if we let x = k?
That wasn't so bad... but, they get worse!
Let's get your brain thinking the right way... Then it will be easy!
Think of it as
This function guy takes any blob... squares it... then adds 5! So...
Whoa, dude! You just got tricked into doing one of the hardest things in Algebra!