The problem asks us to expand and simplify the given expressions involving products of two binomials. I will solve question 10. The problem is to simplify $(k-11)(k+11)$.

1. Problem Description

The problem asks us to expand and simplify the given expressions involving products of two binomials. I will solve question

1

0. The problem is to simplify $(k-11)(k+11)$.

2. Solution Steps

We need to expand the expression $(k-11)(k+11)$.

This is in the form of $(a-b)(a+b)$, which is a difference of squares.

The formula for the difference of squares is:

$(a-b)(a+b) = a^2 - b^2$

In our case, $a=k$ and $b=11$. Therefore, $(k-11)(k+11) = k^2 - 11^2 = k^2 - 121$.

3. Final Answer

$k^2 - 121$