no
Yes.
90 degree triangles are always similar.
All equiangular triangles are similar, but not congruent. They all have three 60 degree angles. This does not mean that they all have the same side lengths though. Therefore, they are only similar, not congruent.
If one corner is right, the other corners are together 90 degrees. So they're both still variable. So: no not all right triangles are similar
No not all obtuse triangular are similar. :)
similar triangles have all the same angles in each of them, and their sides can be of any length
Only right triangles.
no
Yes.
yes
No.
hi
No.
90 degree triangles are always similar.
NO! Only REGULAR Pentagons. All equilateral triangles are similar!!!
No. Only right triangles do, and not all triangles can be right triangles. Equilateral triangles, for example, are always 60°-60°-60°. Isosceles and scalene triangles can be right triangles; all isosceles triangles have the additional useful property of being able to be split into two right triangles.