$\"\"$

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The height of the shell in feet given by formula is $\"\"$ , where t represents the time in seconds after launch.

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Factors the GCF from each group.

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$\"\"$

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The shell $\"\"$ s height at 0 feet, so $\"\"$ .

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Apply zero product property: $\"\"$ .

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$\"\"$ . $\"\"$

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Solve the second equation, $\"\"$ .

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Add 16t to each side.

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$\"\"$

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$\"\"$

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Divide each side by 16.

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$\"\"$

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$\"\"$

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$\"\"$

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The shell $\"\"$ s height at 0 feet when $\"\"$ . $\"\"$

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The value of $\"\"$ substitute in original equation $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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The value of $\"\"$ substitute in original equation $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$ .

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At 10 seconds, the shell is falling. $\"\"$

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(a)The factor form of expression is $\"\"$ ,

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(b)The shell $\"\"$ s height at 0 feet when $\"\"$ ,

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(c)The height after 8 second is $\"\"$ and 10 seconds $\"\"$ and \ \

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(d)At 10 seconds, the shell is falling.