Question

classify the four angles of the quadrilateral.

Explanation:

Step1: Recall angle definitions

• Right angle: \(90^{\circ}\)
• Acute angle: \(0^{\circ}<\theta <90^{\circ}\)
• Obtuse angle: \(90^{\circ}<\theta <180^{\circ}\)

Step2: Classify each angle

• \(\angle A = 90^{\circ}\), so it is a right angle.
• \(\angle B=100^{\circ}\), since \(90^{\circ}<100^{\circ}<180^{\circ}\), it is an obtuse angle.
• \(\angle C = 80^{\circ}\), as \(0^{\circ}<80^{\circ}<90^{\circ}\), it is an acute angle.
• \(\angle D=110^{\circ}\), because \(90^{\circ}<110^{\circ}<180^{\circ}\), it is an obtuse angle.

Answer:

\(\angle A\): Right, \(\angle B\): Obtuse, \(\angle C\): Acute, \(\angle D\): Obtuse