You can put this solution on YOUR website! This may sound silly, but I think it works.
Imagine you are a point on the line
Then you move a little. what do you see?
The equation says you see
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You keep moving. What is ? There is no way
you can possibly know. The equation tells you
nothing about . What is ? The equation
tells you still.
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The only line that fills these conditions is a vertical
line through the point ( 1,0 )