The product of $(x+5)$ and $(x-5)$ is . If the answer in the blank is $x^2-k$, then write the value of $k$.

Find the factors of $x^2-4x+4$.

Express $24a{b}^2{c}^2$ as product of its factors.

$(7x+3)(7x-4)=49x^2-7x-12$

$(a-1{)}^2=a^2-1$.

$\left(x^2+y^2\right)\left(y^2+x^2\right)={\left(x^2+y^2\right)}^2$

$2p$ is the factor of $8pq$.

Express $24a{b}^2{c}^2$ as the product of its factors.

Express $36x^3{y}^{2}z$ as the product of its factors.