Answer:
Step-by-step explanation:
x-y=11
2x+y=19
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x=y+11
2(y+11)+y=19
2y+22+y=19
3y+22=19
3y=19-22
3y=-3
y=-3/3
y=-1
x-(-1)=11
x+1=11
x=11-1
x=10
Answer: x=10, y=-1. (10, -1).
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-6x+5y=1
6x+4y=-10
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9y=-9
y=-9/9
y=-1
6x+4(-1)=-10
6x-4=-10
6x=-10+4
6x=-6
x=-6/6
x=-1
Answer: x=-1, y=-1. (-1, -1).
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2x+9y=25
-4x-9y=-23
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-2x=2
x=2/-2
x=-1
2(-1)+9y=25
-2+9y=25
9y=25-(-2)
9y=25+2
9y=27
y=27/9
y=3
Answer: x=-1, y=3. (-1, 3).
