Answer:
Step-by-step explanation:
3x+4y=5
6x+8y=10
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-2(3x+4y)=-2(5)
6x+8y=10
----------------
-6x-8y=-10
6x+8y=10
------------------
0=0
Answer: Infinitely many solutions.
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7x-2y=9
7x-2y=13
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-1(7x-2y)=-1(9)
7x-2y=13
---------------------
-7x+2y=-9
7x-2y=13
-------------
0=4
Answer: NO Solution.
-------------------------------------
2x-y=-11
-2x+y=11
-----------------
0=0
Answer: Infinitely many solutions.
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3x+6y=1
x+y=0
x=0-y=-y
3(-y)+6y=1
-3y+6y=1
3y=1
y=1/3
x=-y=-1/3
Answer: x=-1/3, y=1/3. (-1/3, 1/3).
