7.2 Solving Systems of Equations Algebraically

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11Solve by Substitution

Examples

Practice Problems

Definitions System of Equations

2 or more equations on the same coordinate system

Consistent System Graph of equations cross each other (not parallel) System has a solution Slope is different

Inconsistent System Graph of equations do not cross each other

(parallel) System does not have a solution Slope is the same

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Consistent System Has a solution at (1,2)

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(1,2)

Inconsistent System No Solution

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Solve by Substitution Steps

Solve for x in the first equation Substitute the answer in for x in the second

equation Solve for y Substitute the value of y into either of the

original equations Solve for x Take the value of x and y and put them in

ordered pair form (x,y)

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Solve by Substitution Example

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Solve by Substitution Example (Cont.)

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Practice Problems Page 379

Problems 11-27

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