# What's the least number of straight lines across America do you need to intersect every state?

Is there an easy way to work out a problem like this

Why does this need only one line
http://oi57.tinypic.com/nlefmc.jpg

But this needs two
http://oi58.tinypic.com/qn04za.jpg

Observing members: 0 Composing members: 0

You need just one.
Just place some black holes at the appropriate positions.
They will warp spacetime, so from an outside reference frame, the line will have curves, but from the reference frame of the line itself, it will be completely straight.
Alternatively, if you mean ‘on a world map’ just angle the line ever so slightly, and when it loops around it will intersect every state, and depending on the angle, even every point on the map.

ragingloli (47294)

A straight line has no curvature. If the slope of the line must be constant, then you’d need to start looking at secant lines since earth is an ellipsoid. It would be less than 25 lines, though. This is because you can (and should) have the secant line intersect at two or more borders, such as the four corners.

dxs (15091)
gailcalled (54577)

we are not assuming it’s on a globe sorry should have said.

or