if the length of one side of a triangle is 5, which of following can't be lengths of other 2?
a 3 and 3
b 3 and 5
c 7 and 8
d 7 and 3
e 7 and 12
what's the correct answer? what rule tells you how to solve this?
2007-11-30 17:35:52 · 6 answers · asked by helen 2 in Science & Mathematics ➔ Mathematics
Sure. The simple rule is that two sides must sum to more than the third side. So
3 3 5 - ok
3 5 5 - ok
7 8 5 - ok
7 3 5 - ok
7 12 5 - no
.
2007-11-30 17:39:08 · answer #1 · answered by tsr21 6 · 0⤊ 0⤋
The rule for a problem of this sort is:
If you add and subtract two sides of the triangle, the third side will be BETWEEN the sum and difference.
ex: a. 3+3 =6
3-3=0
Therefore, this is a possible answer because 5 is between 6 and 0.
So, the answer of this problem would be e. 7 and 12 because 5 is not between 19 and 5.
Hope this helps :)
2007-12-01 01:49:00 · answer #2 · answered by Devi 2 · 0⤊ 0⤋
the answer is E
If one side is 5 and another side is 7 then they add up to 12
if the included angle is 180 deg, then the 5+7 would be a straight line of length 12. The third side is also 12, so you can not make a triangle out of this combination of lengths. The rule is, can you connect the third side using any angles?
2007-12-01 01:46:26 · answer #3 · answered by Rich 7 · 0⤊ 0⤋
e. 7 and 12 is the answer, since 5+7 = 12. For any triangle, the sum of any two sides should be larger than the third side.
2007-12-01 01:40:35 · answer #4 · answered by sahsjing 7 · 0⤊ 0⤋
e. 7 and 12
visualize it --- if one side was 5 and the other 7 they would lay flat against the 12 side, together they would not be long enough to make a shape.
2007-12-01 01:41:37 · answer #5 · answered by lisa b 3 · 0⤊ 0⤋
what kind of triangle is it..the irregular ones? if it is then it coud be B.
2007-12-01 01:38:59 · answer #6 · answered by Lola 2 · 0⤊ 0⤋