Solve the following system of linear equations in three variables.

$3x-2y+z=2, 2x+3y-z=5, x+y+z=6$.

Solve: $\frac{1}{2x}+\frac{1}{4y}-\frac{1}{3z}=\frac{1}{4}; \frac{1}{x}=\frac{1}{3y}; \frac{1}{x}-\frac{1}{5y}+\frac{4}{z}=2\frac{2}{15}$

Find the GCD of the polynomials $x^3+x^2-x+2$ and $2x^3-5x^2+5x-3$.

Find the GCD of $6x^3-30x^2+60x-48$ and $3x^3-12x^2+21x-18$.

Find the LCM of the following

$8x^4{y}^2, 48x^2{y}^4$

Reduce the following rational expression to its lowest form

$\frac{x^2-16}{x^2+8x+16}$

Find the excluded value(s) of the following expression (if any).

$\frac{x}{x^2+1}$

Multiply $\frac{x^3}{9y^2}$ by $\frac{27y}{x^5}$

Multiply $\frac{x^4{b}^2}{x-1}$ by $\frac{x^2-1}{a^4{b}^3}$.