In an isosceles triangle, what can be said about the angles?

In an isosceles triangle, it is defined by having at least two sides that are of equal length. The angles opposite these equal sides are also equal in measure. This property stems from the fact that in any triangle, the interior angles must sum up to 180 degrees. Consequently, if two angles are equal, the third angle can be determined by subtracting the sum of the two equal angles from 180 degrees.

Thus, the statement that two angles are equal accurately describes the properties of an isosceles triangle, making it a distinguishing characteristic of such triangles. In contrast, other options do not align with the properties of an isosceles triangle; for instance, having all angles equal would refer to an equilateral triangle, while stating no angles are equal describes a scalene triangle. Denoting one angle as 90 degrees does not inherently relate to isosceles triangles, as they can have various angle measures, including both acute and obtuse angles.