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#1 2017-10-30 14:20:30

emmakatecumbo
Member
Registered: 2017-09-22
Posts: 30

geometry help

I need help on these few problems i got wrong. I put teachers comments down below.

8. Each set of numbers below represents the lengths of three line segments.
Which set represent line segments that could be connected to form a triangle? Give the reasoning or show your work to support your choice
A. (3, 5, 7)
B. (3, 4, 8)
C.(1, 4, 6)
D. (1, 3, 5)
E. (5, 6, 11)
F. (1, 10, 20)
 
 
9. Each set of numbers below represents the lengths of three line segments.
Which set represent line segments that could be connected to form a triangle?  Give the reasoning or show your work to support your choice
A. (2, 2, 5)
B. (5, 4, 1)
C.(5, 10, 15)
D. (7, 10, 16)
E. (2, 3, 5)
F. (5, 10, 25)
 
19. Here are two triangles. I am trying to measure the area of triangle ABC. The formula for area of a triangle is
base*height/2.


I know the base, but I need to find the height. I know the top of triangle ABC is directly above a point 4.5 units from point A. I also know that


What is the triangle's height? 19.31 square units

 
20. The sun is shining and I am on a hill. I want to measure the height of a tree downhill from me, using my one-meter stick, and a tape measure for measuring shadows. What do I do to take the slope of the hill into account? Not possible
 


Teacher Comments on work :

#8-9   incorrect... what is the RULE?
#19    this is the AREA... use it to find the HEIGHT... show all work
#20    this is just asking if you need to do anything special to take slope into account when you and the tree are on the SAME hill

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#2 2017-10-30 20:25:27

zetafunc
Moderator
Registered: 2014-05-21
Posts: 2,123
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Re: geometry help

Hi emmakatecumbo,

Let's start with the first question. In any triangle, the sum of any two sides must be longer than the third side. (This is called the triangle inequality.)

For example, (3,5,7) can be a triangle, because:

3 + 5 > 7
3 + 7 > 5
5 + 7 > 3

Can you do the rest?

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#3 2017-10-31 13:42:06

emmakatecumbo
Member
Registered: 2017-09-22
Posts: 30

Re: geometry help

So number 9 would be D.
7 + 10 > 16
10 + 16 > 7
16 + 7 > 10

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#4 2017-11-06 01:02:04

zetafunc
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Registered: 2014-05-21
Posts: 2,123
Website

Re: geometry help

Correct! How about the others?

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#5 2017-11-06 02:53:49

emmakatecumbo
Member
Registered: 2017-09-22
Posts: 30

Re: geometry help

I don't know how to do number 19. and 20 sad

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#6 2017-11-06 05:09:45

zetafunc
Moderator
Registered: 2014-05-21
Posts: 2,123
Website

Re: geometry help

It looks like you are missing part of the question for #19.

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