Every triangle have three angles that add up to 180°. With this information, we can find out the missing angle.
The sum of three angles should add up to 180°.
148° + 11° + K = 180°
Where k is the missing angle.
Solve for K.
Combine like terms.
148° + 11° + K = 180°
159° + K = 180°
Subtract both sides by 159°.
159° + K = 180°
159° - 159° + K = 180° - 159°
K = 21°
So, the missing length is 21°.