# Planes in R3 Properties

Hello I am having a problem with the following question.

## Homework Statement

Determine which statements are true in 3. (Select all that apply.)

(a) Two lines parallel to a third line are parallel.
(b) Two lines perpendicular to a third line are parallel.
(c) Two planes parallel to a third plane are parallel.
(d) Two planes perpendicular to a third plane are parallel.
(e) Two lines parallel to a plane are parallel.
(f) Two lines perpendicular to a plane are parallel.
(g) Two planes parallel to a line are parallel.
(h) Two planes perpendicular to a line are parallel.
(i) Two planes either intersect or are parallel.
(j) Two lines either intersect or are parallel.
(k) A plane and a line either intersect or are parallel.

None.

## The Attempt at a Solution

This is what I did (i am going to write it with T/F)
a) F - they maybe skew
b) T
c) T
d) T
e) F - they maybe skew
f) T
g) F - they may intersect
h) T
i) T
j) F - Skew
k) T? - I choose true but a line can be contained in a plane. Are they different things? Or I have a problem in other answers.

Gasim

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Dick
Homework Helper
If by '3' you mean three dimensional euclidean space, then a) is already wrong. What's your definition of parallel? Can you give an example where the two lines are skew?

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if two lines are skew they are neither intersecting nor are parallel

Dick
Homework Helper
if two lines are skew they are neither intersecting nor are parallel

Oh. Sorry. I'll draw it tonight. I just have to rush to a store right. Sorry about that. Thanks.

Dick
Homework Helper
Oh. Sorry. I'll draw it tonight. I just have to rush to a store right. Sorry about that. Thanks.
S'ok, but you'll probably have to do more than draw it. That wouldn't likely be useful. State the definition in words.

Actually, I get it. A is true but B is false. Am I right on this?

Skew is like one of them for example is a straight line to the right and the other one in the bottom of it towards me. Its not a good example but I hope its right.

Dick