Question

Use the substitution method to solve the system of equations. Choose the correct ordered pair. 

Answer 1

Answer:  [B]:  " (-6, 9) " .
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Explanation:
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Given the following system of equations:
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x + y = 3 ;

y = 9 ;
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Substitute "9" for "y" in the first equation; to solve for "x";  we already have our value for "y" ;   "y = 9 " ; (given) ;

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      x + 9 = 3 ;

Subtract "9" from EACH side of the equation;
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     x + 9 − 9 = 3 − 9 ;

to get:
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         x = -6 .
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Check our  answer:

x + y = 3
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-6 + 9 =? 3 ?   Yes!
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The answer for the system of equations is: 
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     x = -6,  y = 9 ;  or, write as:  (-6, 9) .
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   which is:  Answer choice:  [B]:  " (-6, 9) " .
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