Respuesta :

Answer:

m∠ADC = 132°

Step-by-step explanation:

From the figure attached,

By applying sine rule in ΔABD,

[tex]\frac{\text{sin}(\angle ABD)}{\text{AD}}=\frac{\text{sin}(\angle ADB)}{AB}[/tex]

[tex]\frac{\text{sin}(120)}{35}=\frac{\text{sin}(\angle ADB)}{30}[/tex]

sin(∠ADB) = [tex]\frac{30\text{sin}(120)}{35}[/tex]

                 = 0.74231

m∠ADB = [tex]\text{sin}^{-1}(0.74231)[/tex]

             = 47.92°

             ≈ 48°

m∠ADC + m∠ADB = 180° [Linear pair of angles]

m∠ADC + 48° = 180°

m∠ADC = 180° - 48°

m∠ADC = 132°