hey need some help with a question im struggeling with:

The equation of a curve is y=f( x ) where f( x )= x2 - 6x +14

a ) complete the square for f, ( x )

b) Hence Sketch the graph of y = f ( x ) and y = f(x+3)

Whats really confusing me is how to complete the square, usually im ok with this as there are two terms for example

Y = ax + bx

y= ax - bx

to that idea, anyway i cant see a way of there being two sets so just need a lil explaining thanks ^^