Question

which of the following does not have a measure of 40 degrees?
∠aox
∠coa
∠doa

Explanation:

Step1: Find the measure of \(\angle AOX\)

From the diagram, \(\angle AOX = 40^{\circ}\) as it is directly marked.

Step2: Find the measure of \(\angle COA\)

\(\angle COA=\angle COX - \angle AOX\). Since \(\angle COX = 80^{\circ}\) and \(\angle AOX = 40^{\circ}\), then \(\angle COA=80 - 40=40^{\circ}\)

Step3: Find the measure of \(\angle DOA\)

\(\angle DOA=\angle DOX-\angle AOX\). Since \(\angle DOX = 120^{\circ}\) and \(\angle AOX = 40^{\circ}\), then \(\angle DOA=120 - 40 = 80^{\circ}\)

Answer:

\(\angle DOA\)