Understanding Linear Equations
Learning the standard form of a linear equation in two variables.
Core concept
For example, the equation 2x+3y=6 is satisfied by infinitely many ordered pairs, including (0,2), (3,0), and (1.5,1) — each can be verified by substitution. This concept of multiple solutions to a single equation is a key difference from equations in one variable, and understanding it prepares students for studying pairs of simultaneous equations, where finding a solution that satisfies TWO equations at once narrows down the infinite possibilities to typically just one unique solution.
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• A linear equation in two variables: ax+by+c=0.
• It has infinitely many solutions, each an ordered pair (x,y).
• Example: 2x+3y=6 is satisfied by (0,2), (3,0), (1.5,1), and infinitely more pairs.
• This concept leads into studying simultaneous equations, which narrow solutions to a unique pair.