Answer:
x = 16
m∠BDC = 51°
Step-by-step explanation:
m∠ADC = 74°
m∠ADC = (x + 7)° + (2x + 19)°
Then:
(x + 7)° + (2x + 19)° = 74°
x + 2x + 7 + 19 = 74
3x + 26 = 74
3x = 74 - 26
3x = 48
x = 48/3
x = 16
And, the measure of m∠BDC:
m∠BDC = (2x + 19)°
m∠BDC = 2*16 + 19
m∠BDC = 51°
