Answer:
∵ ABC is an isosceles triangle
∵ m∠b = m∠c
∴ m∠b and m∠c = 180 - m∠a/2
= 180 - 50/2
= 130 /2
= 65°
∵ ∠c and ∠AMI are corresponding angles
∵ m∠AMl = m∠c = 65° (1)
From (1)
∵ ∠AMC is striaght angle
∴ m∠IMC = 180 - m∠AMI
m∠IMC = 180 - 65
m∠IMC = 115°
Answer = 115°
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