Here's the question you clicked on:
kylea
geometry question?
The first one is not similar because the sides are not in proportion. 3 can correspond to the 6 (x2) but if you apply the same thing to the 2 (2x2=4), you don't get 5. So they're not similar
For the 2nd one, 10+5=15 and 14+7=21. 10 and 14 (sides of the other triangle) relate to 15 and 21 because 10/14=15/21. You know this cuz you can simplify them both to 5/7
okay i get that but how do you know what they are similar by? is it sss?
Oh. The similarity theorem is always by AA. SSS is if the numbers for the triangles are the same because it proves that the triangles are congruent.
always? let me show you this other problem... would it be AA for it to?
|dw:1341959357505:dw| That would be by SAS
As for your problem, it would be AA because you see that 2 angles are already congruent and you know that there's another set of congruent angles by (Vertical angles are congruent)
GIH and JIK are the vertical angles, btw