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2 years ago

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

Mathematics

1 answer:

poizon [28]2 years ago

4 0

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

y = 9 ;
_________________________________

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

____________________________
      x + 9 = 3 ;

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

to get:
_____________________________________
         x = -6 .
_____________________________________

Check our answer:

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

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