Chapter 9 Systems of Equations

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Chapter 9Systems of Equations
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What is a system of equations?

• Two or more equations in the same variables

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To solve a system

• Find all ordered pairs (x, y) that make both
  equations true

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Methods to Solve

1. Graphing method
2. Substitution method
3. Linear combination/Elimination method

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Solutions

1. One solution
2. No solution
3. Infinitely many solutions

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Calculator Directions

• Rewrite both equations in slope-intercept form,
  if needed.
• Isolate y
• Enter equations in y
• Graph
• Change window, if needed.
• Hit 2nd Trace (Calculate)
• Intersect (5) then hit enter 3 times

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Graphing Method

• Graph each line on the same coordinate plane.
• If lines intersect, there is only one solution
  the intersection point.
• If lines are parallel, there is no solution.
• If lines coincide, there are infinitely many
  solutions.