SOLUTION: 1. If there are 7 points in a plane, no three of which are collinear, how many distinct lines can be formed by connecting two of those points>
a. 18 b.20 c.21 d.22
2. How many
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Question 1088488: 1. If there are 7 points in a plane, no three of which are collinear, how many distinct lines can be formed by connecting two of those points>
a. 18 b.20 c.21 d.22
2. How many combinations of three dishes can be prepared if you have the recipes for 10 dishes?
Answer by ikleyn(52787) (Show Source): You can put this solution on YOUR website!
.
1. If there are 7 points in a plane, no three of which are collinear, how many distinct lines can be formed
by connecting two of those points ?
a. 18
b. 20
c. 21
d. 22
You can draw one and only one straight line through each pair of these points.
Therefore, the answer is = 7*3 = 21.
It is the number of combination of 7 items taken 2 at a time: = 21.
On Combinations, see the lessons
- Introduction to Combinations
- PROOF of the formula on the number of Combinations
- Problems on Combinations
in this site.
Also, you have this free of charge online textbook in ALGEBRA-II in this site
- ALGEBRA-II - YOUR ONLINE TEXTBOOK.
The referred lessons are the part of this online textbook under the topic "Combinatorics: Combinations and permutations".
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