AB=AC
please help with this problem
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Answer:
30°
Step-by-step explanation:
∠CKB = 180 - 110 = 70°
∠KBC = 180° - ∠CKB - ∠KCB
∠KBC = 180° - 70° - 40°
∠KBC = 70° = ∠ABC
given AB = AC (isosceles triangle)
hence ∠ACB = ∠ABC = 70° (base angles of an isosceles triangle)
therefore,
∠ACK = ∠ACB - ∠KCB
∠ACK = 70 - 40 = 30°