Question

If triangle DEF has a 90° angle at vertex E, which statements are true? Select two options.

Triangle DEF is an obtuse triangle.
The angle at vertex D is acute.
The angle at vertex F is obtuse.
Triangle DEF is a right triangle.
The angle at vertex D is obtuse.

Answer 1

Correct choices:
- The angle at vertex D is acute.
- Triangle DEF is a right triangle.

Reason: A 90° angle at E makes the triangle a right triangle, and the other two angles (D and F) must be acute because their measures sum to 90°.