Question

classify the four angles of the quadrilateral.

a
b
c
d
105°
75°
90°
90°

Explanation:

Step1: Recall angle - type definitions

Right angle = 90°, Acute angle < 90°, Obtuse angle > 90° and < 180°.

Step2: Classify ∠A

∠A = 90°, so it's a right angle.

Step3: Classify ∠B

∠B = 105°, so it's an obtuse angle.

Step4: Classify ∠C

∠C = 75°, so it's an acute angle.

Step5: Classify ∠D

∠D = 90°, so it's a right angle.

Answer:

∠A: Right
∠B: Obtuse
∠C: Acute
∠D: Right