https://www.khanacademy.org/math/algebra-1-essentials/x92baf3309dbf8751:systems-of-equations-and-inequalities 2026-06-30T17:30:43.834984468Z Systems of equations and inequalities If one line is useful, let's see what we can do with two lines. In this unit, we learn how to write systems of equations and inequalities, solve those systems, and interpret what those solutions mean in a real-world context. unit