# Thread: line, plane and space

1. ## line, plane and space

write A if the statement is ALWAYS TRUE, S if the statement is SOMETIMES TRUE, and N if the statement is NEVER TRUE.

A 1. a point separates a line into two opposite rays.
A 2. If a single point is removed from a plane, then the remaining points from a
convex set.
No answer 3. There are at least 8 sets into which space can be separated by
four different planes'
S 4. Two circles must intersect in a point.
S 5. Three angles lying in one plane may have a common side.
A 6. If the sides of two angles are two pairs of opposite rays then the angles form a
linear pair.
A 7. A supplementary pair consist of an acute and an obtuse angle.
S 8. If three points are coplanar then they must be collinear.
N 9. A complementary pair is a supplementary pair.
A. 10. A half plane contains its edge.

Gud Day !!! Here's another problem..i try to answer these question yet i have doubt of answer. Can anyone please check my work? Thank you so much

2. Originally Posted by jam2011
write A if the statement is ALWAYS TRUE, S if the statement is SOMETIMES TRUE, and N if the statement is NEVER TRUE.

A 1. a point separates a line into two opposite rays.
yes.

A 2. If a single point is removed from a plane, then the remaining points from a
convex set.
?? There is no verb in the conclusion! Added: Oh! "form", not "from". A convex set has the property that, if two points are in the then so is the line segment between them. Imagine a circle with center at the "removed" point and two points at the ends of a diameter.

No answer 3. There are at least 8 sets into which space can be separated by
four different planes'
The three coordinate planes in a coordinate system divide space into 8 sets.

S 4. Two circles must intersect in a point.
Yes.

S 5. Three angles lying in one plane may have a common side.
Yes.

A 6. If the sides of two angles are two pairs of opposite rays then the angles form a
linear pair.
No! Look up the definition of "linear pair" and contrast it with "vertical angles".

A 7. A supplementary pair consist of an acute and an obtuse angle.

S 8. If three points are coplanar then they must be collinear.
Okay- can be but dont have to be.

[qiote]N 9. A complementary pair is a supplementary pair.[/quote]

A. 10. A half plane contains its edge.
That contradicts the definition of "half plane" given here:
What definition are you using?

Gud day! Here's another problem..i try to answer these question yet i have doubt of answer. Can anyone please check my work? Thank you so much

2. If a single point is removed from a plane, then the remaining points form a
convex set_____________thanks for the correction...not from but "form".....yet im confused what would be my best answer.....maybe the answer SOMETIMES TRUE...PLEASE CHECK.THANKS

3.There are at least 8 sets into which space can be separated by
four different planes' _________________SOMETIMES TRUE>>>>PLEASE CHECK

6. If the sides of two angles are two pairs of opposite rays then the angles form a