True or false? a triangle with one obtuse angle must also have two acute angels?

Alex drew a circle with right triangle prq inscribed in it, as shown below: the figure shows a circle with points p, q, and r on it forming an inscribed triangle. side pq is a chord through the center and angle r is a right angle. arc qr measures 80 degrees.

Use set builder notation to represent the following set: { -3, -2, -1, 0}

Which best explains why this triangle is or is not a right triangle?