Then for the obtuse triangle let w be the obtuse angle then x will be the two acute angles.
From the tierneylab.blogs.nytimes.com
The obtuse isosceles triangle highlighted via the colored lines in the illustration is a golden gnomon.
From the en.wikipedia.org
When one thinks of a triangle, likewise, it is always obtuse, right-angled or acute.
From the en.wikipedia.org
Fat triangle is obtuse and skinny triangle is acute, so x must be acute because it is in both triangles, and must be the angle opposite the equal sides in the fat triangle.