College Algebra I Essay, Research Paper
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)