\(5 k^{2} + 6 k -6 + (-9 k^{2} -9 k -9)\)
Operations with Polynomials
Add quadratic expressions
Simplify each of the following expressions.
Understand that polynomials form a system analogous to the integers, namely, they are closed under the operations of addition, subtraction, and multiplication; add, subtract, and multiply polynomials.