1. The problem asks to categorize triangles based on their angles: acute, obtuse, or right. 2. Definitions: - Acute triangle: all angles less than 90 degrees. - Obtuse triangle: one angle greater than 90 degrees. - Right triangle: one angle exactly 90 degrees. 3. Given figures: - Figures with right angle markers are right triangles. - Figures with all angles less than 90 degrees are acute triangles. - Figures with one angle greater than 90 degrees are obtuse triangles. 4. Categorization: - Triangles with all acute angles: figures 2, 5, 6. - Triangles with an obtuse angle: figure 4. - Triangles with one right angle: figures 1, 3. Final answer: - Acute triangles: 2, 5, 6 - Obtuse triangle: 4 - Right triangles: 1, 3