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Quetion: y= -3x , y 3x=2
Answer: substitute y= -3x in for the y in y 3x=2
y 3x=2
-3x 3x=2
0=2
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Question: x 4y=3 , 2x 8y= -6
Answer: find what x equals
x 4y=3
x 4y -4y=3 -4y
x= -4y 3
then substitute the answer that you got for x into the problem
2x 8y= -6 and solve for y then the answer you got for y put it in
x= -4y 3
and your answer should be ~ -3=-3 which means anything works it's an IDENTITY
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question : x -y=20 , 2x 3y=0
Answer : find y
x -y=20
x -x -y=20 -x
-y= -x 20
If you do the same thing but find x instead of y you'll get
x=y 20
so, you have -y= -x 20 , x= y 20
Substitute -y= -x 20 in for the equation x= y 20
should look like this when you substitute: x= -x 20 20
and you end up with the answer: x=20
So, x= 20
take the equation -y= -x 20 and substitute x in for the x in the equation
looks like this: -y= -20 20
then you end up with: -y=0
then, x=20 , y=0
If your graphing it your coordinates would be: (20,0)
Word Count: 240
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