Short Answer; it pretty much has to be Isosceles.
Let the smallest angle (represented by 1) be x
Then the other two angles are 2x and 2x
Every triangle has 180o and 3 angles.
x + 2x + 2x = 180
5x = 180 Divide by 5
x = 180/5
x = 36
Therefore the angles are
36
72
72
Two angles are the same. The triangle is Isosceles.
