Question

factorizar.
y^{2}-4y + 4

Explanation:

Step1: Identify the form

This is a quadratic trinomial of the form $a^2 - 2ab + b^2$. Here $a = y$ and $b = 2$ since $y^2=a^2\Rightarrow a = y$, $4=b^2\Rightarrow b = 2$ and $4y=2ab$.

Step2: Apply the perfect - square formula

The perfect - square formula is $a^2-2ab + b^2=(a - b)^2$. Substituting $a = y$ and $b = 2$ into the formula, we get $(y - 2)^2$.

Answer:

$(y - 2)^2$