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virtus
 2 years ago
9 dots are drawn as below. How many triangles can be formed by joining three dots?
virtus
 2 years ago
9 dots are drawn as below. How many triangles can be formed by joining three dots?

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virtus
 2 years ago
Best ResponseYou've already chosen the best response.1@UnkleRhaukus hope your not here to troll me again

UnkleRhaukus
 2 years ago
Best ResponseYou've already chosen the best response.0thats not my style @virtus

UnkleRhaukus
 2 years ago
Best ResponseYou've already chosen the best response.0i can see four 2x2 triangles

UnkleRhaukus
 2 years ago
Best ResponseYou've already chosen the best response.0i suppose the dont have to be right angles

ash2326
 2 years ago
Best ResponseYou've already chosen the best response.0@virtus do you have options?

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

virtus
 2 years ago
Best ResponseYou've already chosen the best response.1@UnkleRhaukus you have PARTIALLY redeemed yourself

UnkleRhaukus
 2 years ago
Best ResponseYou've already chosen the best response.0i feel better already,

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

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

mukushla
 2 years ago
Best ResponseYou've already chosen the best response.19C3 triples which are in the same line=9C38 dw:1342275604359:dw

UnkleRhaukus
 2 years ago
Best ResponseYou've already chosen the best response.0i count eighteen dw:1342275638118:dw

UnkleRhaukus
 2 years ago
Best ResponseYou've already chosen the best response.019,20dw:1342275746454:dw

virtus
 2 years ago
Best ResponseYou've already chosen the best response.1but hows that joining three dots?

UnkleRhaukus
 2 years ago
Best ResponseYou've already chosen the best response.0mukushla is right , we are misusing the straight lines because they are not triangles

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

virtus
 2 years ago
Best ResponseYou've already chosen the best response.1but why is do we minus 8

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

UnkleRhaukus
 2 years ago
Best ResponseYou've already chosen the best response.0this is not a triangle dw:1342276198984:dw
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