First you need to find a common denominator.
3/7 & 5/6 will be multiplied by each others denominators .
18/42 & 35/42
8 18/42
- 7 35/42
= 25/42
4 triangles can be created with 3 points on a line.
20 triangles can be created with 6 points on a line.
30 triangles can be created with 7 points on a line.
Combination has to do with selection.
Note that a triangle has 3 vertices. If there are 4 points on a line, the number of triangles it is possible to create is derived using the combination formula shown as:
![nC_r=\frac{n!}{(n-r)!r!}](https://tex.z-dn.net/?f=nC_r%3D%5Cfrac%7Bn%21%7D%7B%28n-r%29%21r%21%7D)
![4C_3 = \frac{4!}{(4-3)!3!}\\4C_3 =\frac{4\times3!}{3!}\\4C_3=4triangles](https://tex.z-dn.net/?f=4C_3%20%3D%20%5Cfrac%7B4%21%7D%7B%284-3%29%213%21%7D%5C%5C4C_3%20%3D%5Cfrac%7B4%5Ctimes3%21%7D%7B3%21%7D%5C%5C4C_3%3D4triangles)
This means that 4 triangles can be created with 3 points on a line.
For a<u> line with 6 points:</u>
![6C_3 = \frac{6\times 5\times 4\times 3!}{(6-3)!3!}\\6C_3 =\frac{6\times5\times 4\times3!}{3!3!}\\4C_3=20triangles](https://tex.z-dn.net/?f=6C_3%20%3D%20%5Cfrac%7B6%5Ctimes%205%5Ctimes%204%5Ctimes%203%21%7D%7B%286-3%29%213%21%7D%5C%5C6C_3%20%3D%5Cfrac%7B6%5Ctimes5%5Ctimes%204%5Ctimes3%21%7D%7B3%213%21%7D%5C%5C4C_3%3D20triangles)
This shows that 20 triangles can be created with 6 points on a line.
For a<u> line with 7 points:</u>
![7C_3 = \frac{7\times 6\times 5\times 4!}{(7-3)!3!}\\4C_3 =\frac{7\times6\times 5\times4!}{4!3!}\\4C_3=30triangles](https://tex.z-dn.net/?f=7C_3%20%3D%20%5Cfrac%7B7%5Ctimes%206%5Ctimes%205%5Ctimes%204%21%7D%7B%287-3%29%213%21%7D%5C%5C4C_3%20%3D%5Cfrac%7B7%5Ctimes6%5Ctimes%205%5Ctimes4%21%7D%7B4%213%21%7D%5C%5C4C_3%3D30triangles)
This shows that 30 triangles can be created with 7 points on a line.
Learn more here: brainly.com/question/23885729
Answer:
-2
Step-by-step explanation:
Hope It Helps
Answer:B
Step-by-step explanation:
Answer:
1/30
Step-by-step explanation:
5^-1 = 1/5
6^-1 = 1/6
1/5 - 1/6 = 1/30