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Standards/Math/District of Columbia/HSA.REI.C

HSA.REI.C

HSA.REI Reasoning with Equations and Inequalities
HSA.REI.A
HSA.REI.B
HSA.REI.C
HSA.REI.C.5HSA.REI.C.6HSA.REI.C.7HSA.REI.C.8HSA.REI.C.9
HSA.REI.D

Solve systems of equations.

HSA.REI.C.5Prove that, given a system of two equations in two variables, replacing one equation by the sum of that equation and a multiple of the other produces a system with the same solutions.HSA.REI.C.6Solve systems of linear equations exactly and approximately (e.g., with graphs), focusing on pairs of linear equations in two variables.HSA.REI.C.7Solve a simple system consisting of a linear equation and a quadratic equation in two variables algebraically and graphically.HSA.REI.C.8Represent a system of linear equations as a single matrix equation in a vector variable.HSA.REI.C.9Find the inverse of a matrix if it exists and use it to solve systems of linear equations (using technology for matrices of dimension 3 × 3 or greater).
Khan Academy Resources
Quadratic systemsQuadratic system with no solutionsQuadratic systems: a line and a parabolaQuadratic systems: a line and a circle
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