I don’t understand the concept of this problem
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Answer:
This uses the method of elimination/addition.
Step-by-step explanation:
1 (9x + 7y = 15)
-7 (5x + y = -9) <— let’s eliminate y for both equations
9x + 7y = 15
+ -35x - 7y = 63 <— add both of the equations
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- 26x + 0y = 6
(Please let me know if the answer is correct or not)