# line, plane and space

• Jan 16th 2011, 04:59 AM
jam2011
line, plane and space
TRUE OR FALSE
false 1. two coplanar lines are parallel.
false 2. two parallel lines are coplanar.
true 3. non-intersecting segments are parallel.
true 4. non-intersecting rays are parallel.
true 5. skew lines do not intersect.
true 6. two segments contained in parallel rays are coplanar
false 7.two lines that are not skew and do not intersect are parallel
true 8. a segment that does not intersect a line is parallel to the line
true 9. coplanar lines cannot be skew lines
true 10. two lines parallel to a third line are parallel to each other.

GUD DAY....I have tried to answer these questions with my own effort. Can any one please check my work? Thank you so much for your great help!
• Jan 16th 2011, 08:53 AM
Soroban
Hello, jam2011!

Quote:

TRUE or FALSE

false 1. two coplanar lines are parallel. . Correct

Quote:

false 2. two parallel lines are coplanar. . [ No
If two lines are parallel, they lie in the same plane.

Quote:

true 3. non-intersecting segments are parallel. . No
The segments could be like this:

Code:

```               *             /             /           /           *       *---------*```

Quote:

true 4. non-intersecting rays are parallel. . No
The rays could be like this:
Code:

```           ↑           |           |           |           *       *-----------→```

Quote:

true 5. skew lines do not intersect. . Correct

true 6. two segments contained in parallel rays are coplanar . Correct

Quote:

false 7. two lines that are not skew and do not intersect are parallel. . No
If two lines are not skew, they are coplanar.
If they are coplanar and do not intersect, they are parallel.

Quote:

true 8. a segment that does not intersect a line is parallel to the line. . No
The segment and line could be like this:
Code:

```               *             /             /           /           *     - - - - - - - - - -```

Quote:

true 9. coplanar lines cannot be skew lines. . Correct

true 10. two lines parallel to a third line are parallel to each other. . Correct

• Jan 16th 2011, 11:33 AM
HallsofIvy
A crucial problem here was your failure to distinguish between a "segment" and a "line".
• Jan 17th 2011, 02:22 AM
jam2011
THANK YOU for your help. It is very much appreciated. Until next time....God Bless!!!
• Jan 17th 2011, 02:27 AM
jam2011
what do you mean sir? what does it mean by a segment and a line?
• Jan 23rd 2011, 12:39 AM
mr fantastic
Please don't post more than two questions in a thread. Otherwise the thread can get convoluted and difficult to follow. See rule #8: http://www.mathhelpforum.com/math-he...ng-151418.html.