Respuesta :

m<ADC = 112, m<BDC = 12x-3, m<ADB = 6x+7
m<BDC = ?

m<BDC = m<ADC - m<ADB
12x - 3 = 112 -(6x+7)
12x - 3 = 112 -6x - 7
12x + 6x = 105 + 3
18x = 108
x = 108/18
x = 6

m<BDC = 12x-3
m<BDC = 12(6) - 3
m<BDC = 72 - 3
m<BDC = 69

answer m<BDC = 69