In figure BC = CA and ∠A = 40°. Then ∠ACD is...
a)40° b) 80° c) 120° d) 60°
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Answer:
B
Step-by-step explanation:
The size of the exterior angle in a triangle is the sum of interior opposite angles. In this case, it's
Angle ACD=40+40=80° (Exterior angle=sum of int. opp. angles)
Answer:
b. 80°
Step-by-step explanation:
B is 40°
A triangle has 180°
40 + 40 + x = 180
80 + x = 180
x = 100
Since it's a supplementary angle...
180 - 100 = 80