SOLUTION: Please help me solve this equation: y=3x x=3y

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Question 175524: Please help me solve this equation: y=3x
x=3y
Found 2 solutions by solver91311, Alan3354:
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!
I think you mean 'solve this system of equations':

Eq. 1: y+=+3x

Eq. 2: x+=+3y

Put each equation in standard form Ax+%2B+By+=+C

Eq. 1:

y+=+3x
-3x+%2B+y+=+0

Eq. 2:

x+=+3y
x+-+3y+=+0

Multiply Eq. 2 by 3: 3x+-+9y+=+0

Now add term by term to Eq. 1:

0x+-+8y+=+0

-8y+=+0

y+=+0

Substitute into either original equation: x+=+3%280%29+=+0.

The solution set is

This should have been what you expected because you can see by inspection that the y-intercept for both equations is the point and that since the lines have different slopes, this must be a consistent system.

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Please help me solve this equation:
y=3x
x=3y
If you sub for y:
x = 3*3x
1 = 9
There's no solution possible other than x and y are zero.
x = 3*3x
x = 9x
8x = 0
x = 0
y = 0
If you graph these, you get 2 straight lines that intersect at the origin (0,0).