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## Main Question or Discussion Point

I feel like a total noob, but my friend is reviewing distance formula and asked for my help. I can't seem to get the correct answer, which his teacher wrote as (3√5)/5

What is the distance from the line y=2x to the parallel line y=2x+3?

The vertical distance is obviously 3, but that is not what they want. When I try two different x-values, 1 for y=2x and 2 for y=2x+3, I get the following:

(1,2) for y=2x

and

(2,7) for y=2x+3

When I plug those into the distance formula I get √26:

√(2-1)^2 + (7-2)^2

It has been a long time since I did this, what am I forgetting? I am sure it is something simple...

What is the distance from the line y=2x to the parallel line y=2x+3?

The vertical distance is obviously 3, but that is not what they want. When I try two different x-values, 1 for y=2x and 2 for y=2x+3, I get the following:

(1,2) for y=2x

and

(2,7) for y=2x+3

When I plug those into the distance formula I get √26:

√(2-1)^2 + (7-2)^2

It has been a long time since I did this, what am I forgetting? I am sure it is something simple...