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## #51 2012-09-01 17:47:46

bob bundy
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### Re: Naming Geometry Elements

Good morning zee-f and bobbym,

I think 16C too.

I'm going to have a long think about 17.

Back after that.

LATER EDIT:

From Mathswords.com:               angle = Two rays sharing a common endpoint.

I have an angle
=>    I have two rays sharing a common endpoint
=>    I have a common point + another point on ray 1 + another point on ray 2
=>    I have three points
=>    I have a plane

Bob

You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

## #52 2012-09-01 23:23:41

zee-f
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### Re: Naming Geometry Elements

I posted this to my teacher:

15- I choose A-No, because rays need one endpoint

15- Explanation:
Well as mentioned in the lesson because a ray continues indefinitely in one direction, but has a definite endpoint in the other direction, but a line needs two points to define it but it goes beyond these points it doesn't have a starting or ending point it keeps going forever.

she said #15 is incorrect.  If a ray exists, then it contains the two points that are needed to define and name it.  How many points are needed to define and name a line?

am going to submit this as a new answer:

#15- Two points are needed to define and name a line. So the right answer is (E)

15. In figure 1 above, can ry_EH be used to create a line?

E- Yes, because any two points can be used to make a line

But for #17- B, and E were in correct answers.

One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

## #53 2012-09-01 23:35:56

zee-f
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### Re: Naming Geometry Elements

17. If I have an angle, do I have a plane?

17. I choose (F)Yes, because that means you have two lines that meet at a single point.
Explanation:
I have a common point another point on ray 1 + another point on ray 2 now I have three points and rays can be used to create a line. To have a plane two lines have to intersect in a single point, and an angle intersects in a single point.So,
I have a plane.

One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

## #54 2012-09-02 00:40:37

zee-f
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### Re: Naming Geometry Elements

15-E
17-F

I got a 9 from 10

One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

## #55 2012-09-02 02:10:23

bob bundy
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### Re: Naming Geometry Elements

hi zee-f,

Thanks for telling us the answers your teacher was expecting.  I seem to remember, way back, that I thought 15 E was a posible answer.

How are you expecting to be assessed for this work ?  Will you have to do an exam ?

Bob

You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

## #56 2012-09-02 03:10:07

bobbym

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### Re: Naming Geometry Elements

Hi all;

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

zee-f
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