A quadratic trinomial is a polynomial with three terms and degree 2. This post explains how to factoring a simple quadratic trinomial. Students in grade 8 or 9 often encounter these in their curriculum. So these are the most basic forms to build on higher skills on factoring all types of polynomials.
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https://drive.google.com/file/d/0Bx7sFl7hhj8Fc3p3ejJBNUdPZEk/view
