$\"\"$

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The expression is $\"\"$ . \ \

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The formula $\"\"$

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$\"\"$

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$\"\"$ (Substitute x = 8, z = 0.4) \

$\"\"$ (Evaluate power: $\"\"$ )

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

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

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$\"\"$ (Add: 64 + 5.76 = 69.76)

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

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The value of the expression is $\"\"$ .

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