$\"\"$

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Solve the system of equation using Substitution Method:

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The equations are

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$\"\"$ Equation (1)

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$\"\"$ Equation (2)

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Solve the first equation for r in terms of s. $\"\"$

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Apply subtraction property of equality; if a = b, then $\"\"$ .

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$\"\"$ (Subtract 2r from each side)

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Apply commutative property of addition: $\"\"$ .

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$\"\"$

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$\"\"$ (Apply Additive inverse property: $\"\"$ )

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$\"\"$ (Apply Additive identity property: $\"\"$ )

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$\"\"$

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Substitute $\"\"$ in Equation (2).

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$\"\"$

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Distribute terms using distributive property: $\"\"$ .

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$\"\"$

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$\"\"$ (Multiply: $\"\"$ )

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$\"\"$ (Multiply: $\"\"$ )

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Apply commutative property of addition: $\"\"$ .

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$\"\"$

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$\"\"$ (Add: $\"\"$ ) $\"\"$

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Apply addition property of equality; if a = b, then a + c = b + c.

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$\"\"$ (Add 22 to each side)

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$\"\"$ (Apply Additive inverse property: $\"\"$ )

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$\"\"$ (Apply Additive identity property: $\"\"$ )

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$\"\"$ (Add: $\"\"$ )

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$\"\"$

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Apply division property of equality: if a = b, then $\"\"$ .

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$\"\"$ (Divide each side by 10)

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$\"\"$ (Cancel common terms)

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$\"\"$ (Divide: $\"\"$ )

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$\"\"$

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Substitute $\"\"$ in equation $\"\"$ .

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$\"\"$

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$\"\"$ (Multiply: $\"\"$ )

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$\"\"$ (Subtract: $\"\"$ ) $\"\"$

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The solution is $\"\"$ .