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| Question 508576:   Solve each system.
 1. 10x+6y=0
 -7x+2y=31
 
 2. 7x+5y=18
 -7x-9y=4
 3. -3x+y=6
 6x-2y=25
 
 
 
 
 
 
 
 
 
 
 
 
 Answer by Alan3354(69443)
      (Show Source): 
You can put this solution on YOUR website!  Solve each system. 1. 10x+6y=0
 -7x+2y=31
 Multiply the 2nd eqn by 3, then subtract.
 10x +6y=0
 -21x+6y=93
 ------------- Subtract
 31x = 93
 etc.
 ------------
 2. 7x+5y=18
 -7x-9y=4
 -------------- Add them
 ===========================
 ------------
 3. -3x+y=6
 6x-2y=25
 Multiply the 1st eqn by 2
 3.-6x+2y=12
 6x-2y=25
 ---------------- Add
 0 = 37
 That's not true, so the system is inconsistent.
 --> no solution.
 If you graph them, you get parallel lines, no intersection, no solution.
 
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