Answer:
B. 70°
Step-by-step explanation:
If this is an equilateral triangle, then each angle is 180/3 = 60
<A = 60 = x+3x+2x
60 = 6x
60/6 = 6x/6
10 =x
Angle B will also equal 60 degrees
BDA + x + B = 180
BDA + 10 + 60 = 180
BDA + 70 = 180
BDA = 180-70
BDA = 110
BDA and y are complementary angles since they form a straight line
BDA + y = 180
110 +y =1 80
y = 180-110
y = 70
