The expression to simplify is $(y + 4)^2$.

Let's expand the binomial using the formula for squaring a binomial: $(a + b)^2 = a^2 + 2ab + b^2$

Here, $a = y$ and $b = 4$.

Applying this to the given expression:

$(y + 4)^2 = y^2 + 2(y)(4) + 4^2$ $= y^2 + 8y + 16$

So, the simplified expression is: $y^2 + 8y + 16$

In the question format provided, the missing terms are $8$ for the coefficient of $y$, and $16$ for the constant.

Would you like further details or have any questions about this?

Related questions:

1. How do you expand other binomials, like $(y - 3)^2$?
2. Can you apply this expansion technique to trinomials like $(y + 2 + x)^2$?
3. How do you factor a perfect square trinomial?
4. Can the same method be used to expand $(y + 4)^3$?
5. What is the geometric interpretation of squaring binomials?

Tip:

When squaring binomials, always remember to apply the distributive property carefully to avoid missing terms!