y^4-14y^3+49y^2

y^2(y^2-14y+49)
y^2(y-7)^2

if you solve a problem like this ^ then how do you solve this:

x^2-4x+4

?????

x^2-4x+4

= (x-2)^2

how come you got the hard one, but missed the easy one?