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## #1 2017-10-29 10:50:57

emmakatecumbo
Member
Registered: 2017-09-22
Posts: 35

### Geometry help

1. Refer to the image at the right. If angle 1 is 30 degrees, and angle 5 is 70 degrees, are the two lines

parallel? Explain.

1 should = 5 if they are parallel and had a transversel through them.

2. Refer to the image at right. If angle 2 is 30 degrees and angle 4 is 60 degrees, are the lines parallel?

Explain.

co-interior angles are supplementary and thus 6+4 should = 180. 30 and 60 obviously are

complementary, not supplementary.

3. Refer to the image at right. If angle 2 and angle 6 are both 70 degrees, are the lines parallel? Explain.

I have no clue what the answer is for this one.

5. What is the measure of the inner angle of a regular hexagon? Show your work (and be sure to explain

anything you deem necessary to make sure your work is clear.)

A. A hexagon has 6 sides.

180 x 6 = 1080

The sum of the angles of deviation is 360

SO

1080 360 = 720

6. What is the measure of the inner angle of a regular decagon? Show your work (and be sure to explain

anything you deem necessary to make sure your work is clear.)

A. A decagon has 10 sides.

180 x 10 = 1800

The sum of the angles of deviation is 360

SO

1800 360 = 1440

7. Polygon A has sides of 4, 3, 5, and 3. Polygon B has sides of 8, 6, 10, and 6. What are the two possible

scale factors here? Explain.

To get my scale factor, I will need to divide the two polygons. This is how I

will do it along with the answers for each number:

4 / 8 = 1/2

3 / 6 = 1/2

5 / 10 = 1/2

3 / 6 = 1/2

So now we know the scale factor is 1:2.

10. A right triangle has a 90 degree angle, and an angle x. What will the measure of the third angle be?

I believe the answer for this would be 90 x.

Teachers comments on my work :
#1-3    Now state whether or not the lines are parallel

#5-6    What is the measure of ONE angle?

#7    and what is the OTHER possible scale factor for these measurements?

#10    90x means 90*x...  that is incorrect... is there another relationship between 90 and x?

Last edited by emmakatecumbo (2017-10-29 10:51:31)

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## #2 2017-10-29 18:49:12

alter ego
Member
Registered: 2012-03-30
Posts: 27

### Re: Geometry help

Again no diagram for the first three.

You have correctly found the angle sum for the polygons. In a regular polygon all the angles will be equal, so now calculate one of them.

Your scale factor is correct for small shape as a fraction of the large shape.  I think the second answer is for large as a multiple of the small.

In the last a minus sign is needed.  I'm not seeing that.

What course are you studying?

A

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## #3 2017-10-30 03:24:19

Member From: Planet Mars
Registered: 2016-11-15
Posts: 820

### Re: Geometry help

Hi alter ego,

You need to post a diagram for this as well as the other thread. I think you missed it.

Practice makes a man perfect.
There is no substitute to hard work
All of us do not have equal talents but everybody has equal oppurtunities to build their talents.-APJ Abdul Kalam

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## #4 2017-10-30 10:19:51

emmakatecumbo
Member
Registered: 2017-09-22
Posts: 35

### Re: Geometry help

How do you post the diagram

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## #5 2017-10-30 20:26:27

zetafunc
Moderator Registered: 2014-05-21
Posts: 2,242
Website

### Re: Geometry help

Hi emmakatecumbo,

: Videos on various topics.
New:  |
Popular:  |  |

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## #6 2017-10-31 13:40:04

emmakatecumbo
Member
Registered: 2017-09-22
Posts: 35

### Re: Geometry help

https://postimg.org/image/7zi8v9g2hn/

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