Got Homework?
Connect with other students for help. It's a free community.
Here's the question you clicked on:
 0 viewing
9 dots are drawn as below. How many triangles can be formed by joining three dots?
 one year ago
 one year ago
9 dots are drawn as below. How many triangles can be formed by joining three dots?
 one year ago
 one year ago

This Question is Closed

virtusBest ResponseYou've already chosen the best response.1
@UnkleRhaukus hope your not here to troll me again
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.0
thats not my style @virtus
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.0
i can see four 2x2 triangles
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.0
16, 1x1 triangles
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.0
i suppose the dont have to be right angles
 one year ago

ash2326Best ResponseYou've already chosen the best response.0
@virtus do you have options?
 one year ago

virtusBest ResponseYou've already chosen the best response.1
not sure what you mean by options @ash2326 but incase you were wondering, my solution book says 9C3 8
 one year ago

virtusBest ResponseYou've already chosen the best response.1
@UnkleRhaukus you have PARTIALLY redeemed yourself
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.0
i feel better already,
 one year ago

virtusBest ResponseYou've already chosen the best response.1
good to know, why don't you change feeling "good" to "euphoric" by suggesting why the answer is 9C3 8
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.0
say you want to find all the triangle that have the top left as a vertex, how many can you make
 one year ago

mukushlaBest ResponseYou've already chosen the best response.1
9C3 triples which are in the same line=9C38 dw:1342275604359:dw
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.0
i count eighteen dw:1342275638118:dw
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.0
19,20dw:1342275746454:dw
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.0
there are so many
 one year ago

virtusBest ResponseYou've already chosen the best response.1
but hows that joining three dots?
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.0
mukushla is right , we are misusing the straight lines because they are not triangles
 one year ago

mukushlaBest ResponseYou've already chosen the best response.1
different triangles can be formed by joining 3 of the dotes unless 3 dots are in the same line, so C(3,9)8
 one year ago

virtusBest ResponseYou've already chosen the best response.1
but why is do we minus 8
 one year ago

mukushlaBest ResponseYou've already chosen the best response.1
u can count triples of dots that are in the same line just like what i did up there
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.0
this is not a triangle dw:1342276198984:dw
 one year ago
See more questions >>>
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.