Answer:
Arc CDE = 248°
∠CAB = 39°
Arc DCB = 178°
Arc EBC = 126°
Step-by-step explanation:
Question 1
An arc is named using its endpoints. If the arc is named using three letters, the middle letter is any other point contained in the arc.
Therefore, the arc CDE is the sum of arc CD and arc DE:
[tex]\begin{aligned}\overset{\frown}{CDE}&=\overset{\frown}{CD}+\overset{\frown}{DE}\\&=200^{\circ}+48^{\circ}\\&=248^{\circ}\end{aligned}[/tex]
Therefore, arc CDE measures 248°.
As the measure of an arc is equal to the measure of its corresponding central angle, and angles around a point sum to 360°, then:
[tex]\angle CAB+\angle CAD + \angle DAE + \angle EAD = 360^{\circ}[/tex]
[tex]\angle CAB+\overset{\frown}{CD} + \overset{\frown}{DE} + \angle EAD = 360^{\circ}[/tex]
[tex]\angle CAB+200^{\circ}+ 48^{\circ} + 73^{\circ} = 360^{\circ}[/tex]
[tex]\angle CAB+321^{\circ} = 360^{\circ}[/tex]
[tex]\angle CAB=39^{\circ}[/tex]
Therefore, angle CAB measures 39°.
[tex]\hrulefill[/tex]
Question 2
An arc is named using its endpoints. If the arc is named using three letters, the middle letter is any other point contained in the arc.
Therefore, the arc DCB is the sum of arc DC and arc CB:
[tex]\overset{\frown}{DCB}=\overset{\frown}{DC}+\overset{\frown}{CB}[/tex]
The measure of an arc is equal to the measure of its corresponding central angle. Therefore:
[tex]\begin{aligned}\overset{\frown}{DCB}&=\overset{\frown}{DC}+\overset{\frown}{CB}\\&=111^{\circ}+67^{\circ}\\&=178^{\circ}\end{aligned}[/tex]
Therefore, arc DCB measures 178°.
As the measure of an arc is equal to the measure of its corresponding central angle, and angles around a point sum to 360°, then:
[tex]\overset{\frown}{DC} + \overset{\frown}{CB} + \overset{\frown}{BE} +\overset{\frown}{ED}= 360^{\circ}[/tex]
[tex]111^{\circ} + 67^{\circ} + \overset{\frown}{BE} +123^{\circ}= 360^{\circ}[/tex]
[tex]\overset{\frown}{BE} +301^{\circ}= 360^{\circ}[/tex]
[tex]\overset{\frown}{BE} =59^{\circ}[/tex]
The arc EBC is the sum of arc EB and arc BC:
[tex]\begin{aligned}\overset{\frown}{EBC}&=\overset{\frown}{EB}+\overset{\frown}{BC}\\&=59^{\circ}+67^{\circ}\\&=126^{\circ}\end{aligned}[/tex]
Therefore, arc EBC measures 126°.