△ABC has interior angles with measures x°, 100°, and 70°.
By using angle sum property, which states that the sum of measures of all three angles is 180 degrees.


Now, △DEF has interior angles with measures y°, 70°, and 20°.
By using angle sum property,


Now, we can say that,
"The two triangles are not similar because x≠y"
As one angle of measure 70 degree is common in both the triangles.
If 'x' would be equal to 'y' , then we could say that the triangles are similar by AA criteria.
Therefore, the two triangles are not similar because x is not equal to y.