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Lesson 2 of 10

Two lines: cross or never meet

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4 min

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The two rails of a railway track run side by side. Do they ever meet?

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Two lines that cross.
Step 1 of 4
  1. Two lines that cross.
  2. They meet at one point.
  3. Two lines side by side.
  4. The gap stays the same.

The rule

A line goes on for ever. Two lines on a flat page either meet or never meet.

Two lines intersect when they cross. They meet at one point.

Two lines are parallel when they never meet. Parallel lines keep the same gap.

Two lines that lean together will meet, even off the page.

Example

The two rails of a track keep the same gap. They never meet. So the rails are parallel.

A road crosses the track. The road meets each rail at one point. So the road intersects each rail.

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