Hi brash,

> I need find perpendicular to curve and parallel to straight. both points
> are very closly but I need accuracy.)))

You may not have seen my above posts since you were probably writing a reply at the same time I was posting them.

Check up above for how "perp/perp" snap works - I think that's what you want. Place a line or construction line along the x-axis direction below your curve. Then you will be able to draw a line or construction line and engage "perp/perp" snap to find a point on the curve where the curve perpendicular matches the perpendicular to the x-axis direction. That will be a line at a point on the curve where the curve perpendicular and y-axis direction are the same.

There is a video screencap and more explanation in the above posts.

Or also if you use the BoundingBox command to generate a frame around the curve you will then have some intersections at the points you want as well.

- Michael