A set of two or more equations. Each equation contains two or more
variables.

If the measure of xyz is 81 what is the measure of yz

What is the value of m in the equation 1/2 m - 3/4n=16 when n=8

Simplify (4x^2 - 8xy + 2y^2) - (9x^2 - 4xy - 7y^2) a. -5x^2 + 4xy + 9y^2 b. -5x^2 - 4xy + 9y^2 c. -5x^2 + 12xy + 4y^2 d. -5x^2 - 4xy - 5y^2