Discussion about math, puzzles, games and fun. Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ π -¹ ² ³ °

You are not logged in.

- Topics: Active | Unanswered

Pages: **1**

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

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

Offline

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?

**LearnMathsFree: Videos on various topics.New: Integration Problem | Adding FractionsPopular: Continued Fractions | Metric Spaces | Duality**

Offline

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

So number 9 would be D.

7 + 10 > 16

10 + 16 > 7

16 + 7 > 10

Offline

Correct! How about the others?

**LearnMathsFree: Videos on various topics.New: Integration Problem | Adding FractionsPopular: Continued Fractions | Metric Spaces | Duality**

Offline

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

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

Offline

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

**LearnMathsFree: Videos on various topics.New: Integration Problem | Adding FractionsPopular: Continued Fractions | Metric Spaces | Duality**

Offline

Pages: **1**