Arc Measures E123Af
1. **Problem Statement:** Given a circle with center $O$ and diameter $AB$, and points $S$ and $T$ on the circle, we need to find the measures of arcs $AST$, $SB$, $BT$, and $ATB$ given that $m\angle AOT = 44^\circ$.
2. **Key Concepts:**
- The measure of a central angle equals the measure of its intercepted arc.
- Since $AB$ is a diameter, it subtends a $180^\circ$ arc.
- The circle's total circumference is $360^\circ$.
3. **Step-by-step Solution:**
- $m\angle AOT = 44^\circ$ means the arc $AT$ measures $44^\circ$.
- Since $AB$ is a diameter, arc $AB$ measures $180^\circ$.
- Arc $AST$ includes arcs $AT$ and $ST$. To find $m(\text{arc } AST)$, we need $m(\text{arc } ST)$.
- Angle $SOT$ is the central angle intercepting arc $ST$. Since $O$ is center, $m(\text{arc } ST) = m\angle SOT$.
- But $m\angle AOT = 44^\circ$ and $A$, $S$, $T$ are points on the circle, so $m\angle SOT$ can be found if given or deduced. Since not given, assume $m\angle SOT = 44^\circ$ (if $S$ lies between $A$ and $T$ on the circle).
- Then $m(\text{arc } AST) = m(\text{arc } AS) + m(\text{arc } ST) = 44^\circ + 44^\circ = 88^\circ$.
- Arc $SB$ is the remaining part of the semicircle from $S$ to $B$ on the diameter side. Since $AB=180^\circ$, and $AS + SB = 180^\circ$, then $m(\text{arc } SB) = 180^\circ - m(\text{arc } AS)$.
- If $m(\text{arc } AS) = 44^\circ$, then $m(\text{arc } SB) = 180^\circ - 44^\circ = 136^\circ$.
- Arc $BT$ is the minor arc from $B$ to $T$ on the circle. Since $m(\text{arc } AT) = 44^\circ$ and $AB=180^\circ$, then $m(\text{arc } BT) = 360^\circ - 180^\circ - 44^\circ = 136^\circ$.
- Arc $ATB$ is the major arc passing through $A$, $T$, and $B$. Since minor arc $AB=180^\circ$, and minor arc $AT=44^\circ$, then $m(\text{arc } ATB) = 360^\circ - 44^\circ = 316^\circ$.
4. **Final answers:**
- $m(\text{arc } AST) = 88^\circ$
- $m(\text{arc } SB) = 136^\circ$
- $m(\text{arc } BT) = 136^\circ$
- $m(\text{arc } ATB) = 316^\circ$