Question

identify all acute angles in the drawing below.
∠bcd
∠bce
∠ace, ∠ecd
∠acd

Explanation:

Step1: Recall acute - angle definition

An acute angle is an angle whose measure is between 0° and 90°.

Step2: Analyze each angle

• $\angle BCD = 90^{\circ}$, so it is not acute.
• $\angle BCE>90^{\circ}$, so it is not acute.
• $\angle ACE$ and $\angle ECD$ are both less than $90^{\circ}$, so they are acute.
• $\angle ACD = 90^{\circ}$, so it is not acute.

Answer:

$\angle ACE,\angle ECD$