$\"\"$

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The equation is

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$\"\"$

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The matrices have the same dimensions and the corresponding elements are equal.

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The equality can be written as a two linear equations

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$\"\"$ Equation (1)

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$\"\"$ Equation (2)

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$\"\"$

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The first equation is $\"\"$

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According to subtraction property equality: if a=b, then $\"\"$ .

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$\"\"$ (Subtract 2x from each side).

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

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

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$\"\"$

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The second equation is $\"\"$

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$\"\"$ (Replace $\"\"$ in first equation 2).

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$\"\"$ (Apply Distributive property: $\"\"$ )

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

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

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$\"\"$ (Apply Distributive property: $\"\"$ )

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

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$\"\"$

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$\"\"$ (Add 15 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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$\"\"$ (Divide each side by 7)

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$\"\"$ (Cancel common terms)

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

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$\"\"$

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$\"\"$ (Replace x = 4 in equation $\"\"$ )

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

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

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$\"\"$

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The solution is $\"\"$ .

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