Find the value of $x$ in the following equation:

$\left(x-3\right)\left(x+3\right)= 0$

Find the value of $x$ in the following equation:

$\left(3x-6\right)\left(x-5\right)=0$

If one of the values of $x$ in the following equation is $2$, then find the other value.

$\left(2x-8\right)\left(2x-4\right)=0$

Find the value of $x$ in the following equation:

Find the value of $x$ in the following equation:

Factorise: $x^2-6x+9$

If the factorised form of the expression $x^2+12x+36$ is $\left(x+a\right)\left(x+b\right)$, then write the value of $a+b$.

Factorise: $x^2-9$

Factorise: $4x^2-4x+1$