$\"\"$

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The equation is $\"\"$ .

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$\"\"$ (Subtract 4 from each side) \ \

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$\"\"$

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$\"\"$

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Case 1 Case 2

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$\"\"$ $\"\"$

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$\"\"$ (Add 5 to each side)

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$\"\"$

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$\"\"$

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$\"\"$ (Add 5 to each side)

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$\"\"$

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The solutions are 10 and 0. $\"\"$

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Check:

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To check, substitute a = 10 in the original equation $\"\"$ .

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$\"\"$ (Substitute a = 10)

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$\"\"$

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$\"\"$

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To check, substitute $\"\"$ in the original equation $\"\"$ .

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$\"\"$ (Substitute $\"\"$ )

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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The solution set is $\"\"$ .