Given:
m(ar QT) = 220
m∠P = 54
To find:
The measure of arc RS.
Solution:
PQ and PT are secants intersect outside a circle.
If two secants intersects outside a circle, then the measure of the angle formed is one-half the positive difference of the measures of the intercepted arcs.
![$\Rightarrow \angle P = (1)/(2) (m \ ar (QT) - m \ ar (RS ))](https://img.qammunity.org/2021/formulas/mathematics/high-school/y9g04aofvc6z4ubjqrgqqauo9kjkdaffs6.png)
![$\Rightarrow 54 = (1)/(2) (220- m \ ar (RS ))](https://img.qammunity.org/2021/formulas/mathematics/high-school/auoemgrxpcqkkszw6mh7vljngbcf8nvzul.png)
Multiply by 2 on both sides.
![$\Rightarrow 2 * 54 = 2 * (1)/(2) (220- m \ ar (RS ))](https://img.qammunity.org/2021/formulas/mathematics/high-school/bo340vgi0vx7gd4piyj1uscuzlsjqhrc0g.png)
![$\Rightarrow 108= 220- m \ ar (RS )](https://img.qammunity.org/2021/formulas/mathematics/high-school/jd5av3bccukiw5cgl4kd9qyj1473zzrhjz.png)
Subtract 220 from both sides.
![$\Rightarrow 108-220= 220- m \ ar (RS )-220](https://img.qammunity.org/2021/formulas/mathematics/high-school/xg337h762b91isrnyzu1izckcrmf6tgg4r.png)
![$\Rightarrow -112= -m \ ar (RS )](https://img.qammunity.org/2021/formulas/mathematics/high-school/w3kobpwe5inkod4dobjjjioayjv1o2tqw9.png)
Multiply by (-1) on both sides.
![$\Rightarrow (-112)*(-1)= -m \ ar (RS )*(-1)](https://img.qammunity.org/2021/formulas/mathematics/high-school/x92gkzosgoymvdtqeownzyhaexis81b59b.png)
![$\Rightarrow 112= m \ ar (RS )](https://img.qammunity.org/2021/formulas/mathematics/high-school/5jp1a1rh5lzy6w6r62eqymcubi5h5vz1se.png)
The measure of arc RS is 112.