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The equation is $\"\"$ .

Subtract 7a from each side.

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Subtract 15 from each side.

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Divide each side by negative 10.

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

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

$\"\"$

$\"\"$ .

The above statement is true. So the value of $\"\"$ is a solution of the original equation. $\"\"$

The value of $\"\"$ .