# Can you know that 2 triangles are similar if you know that 2 sides are proportional?

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• Can you know that 2 triangles are similar if you know that 2 sides are proportional?

Answer #1 | 13/02 2014 07:42
No You must know that the angle between is equal or that also the third sides are in the same proportion of the other
Answer #2 | 13/02 2014 07:46
If that is all you know about the two triangles, then, no, you cannot say the two triangles are similar. For example, given the two sides of two different triangles as follows: Triangle A: Side a = 10, side b = 5, side c can be any value between 5 and 15 Triangle B: side a = 20, side b = 10, side c can be any value between 10 and 30 The sides a and b of the two triangles are proportional, but side c is not necessarily proportional between the two triangles. If a is 6 in triangle A, then A is an acute triangle and if a is 29 in triangle B, then B is an obtuse triangle. Two of the three sides would be proportional, but the triangles would not be similar.