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)