Question 123674
Find an equation of the line that passes through the points (0,0), (0,10).
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You are given the y-intercept as (0,10)
The slope is (10-0)/(0-0) = 10/0 which is "undefined".
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If the slope is undefined, the line is vertical.
It passes thru two points where x=0 so it must 
pass thru all the points where x=0
It's equation is x=0.
Cheers,
Stan H.