To find the area of a sector of a circle in terms of π having the angle in degrees you use the next formula:
![A=(\theta)/(360)\cdot\pi\cdot r^2](https://img.qammunity.org/2023/formulas/mathematics/college/mzngvkpwtl3uj63gh1v82u30ib99dvbabb.png)
r is the radius
To find area of sector MAG:
1. Find the angle of the sector MAG.
The semicircle has an angle of 180° and it is divided into 3 sectors MAG, GAI, and IAP.
As the arcs MG and IP are congruents (have the same measure) the angles of the sectors MAG and IAP are also congruent.
![\begin{gathered} m\angle\text{MAG}+m\angle\text{GAI}+m\angle\text{IAP}=180 \\ \\ m\angle MAG=m\angle IAP \\ m\angle GAI=30 \\ \\ 2m\angle MAG+m\angle GAI=180 \\ 2m\angle MAG+30=180 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/5ddqtlo098ybstk3xjgpdx8s4oc4huinaa.png)
Use the equation above to find the measure of angle MAG:
![\begin{gathered} 2m\angle MAG=180-30_{} \\ 2m\angle MAG=150 \\ m\angle MAG=(150)/(2) \\ \\ m\angle MAG=75 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/9ua2iyzy3leafqc08028peajcdyyxbs1fy.png)
2. Find the area of sector MAG:
Angle 75°
radius= half of the diameter (26/2 = 13)
r=13
![\begin{gathered} A=(75)/(360)\cdot\pi\cdot(13)^2 \\ \\ A=(75)/(360)\cdot\pi\cdot169 \\ \\ A=(12675)/(360)\pi \\ \\ A=(845)/(24)\pi \\ \\ A\approx35.21\pi \\ \\ A\approx110.61 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/83emlty5vbkz52k62ifeu312flgatods6k.png)
The exact area of the sector MAG is 845/24 π units squared.
Rounded to the nearest hundredth 35.21 π units squared or 110.61 units squared