góc ACK=90-50=40 độ
=>góc IHC=50 độ
=>góc IHK=130 độ
ˆKAI+ˆAIH+ˆIHK+ˆHKA=360oKAI^+AIH^+IHK^+HKA^=360o
ˆIHK=360o−50o−90o−90oIHK^=360o−50o−90o−90o
⇒ˆIHK=130o⇒IHK^=130o
ˆACK=180o−500−90oACK^=180o−500−90o
ˆACK=40oACK^=40o
ˆIHC=180o−90o−40oIHC^=180o−90o−40o
ˆIHC=50o
KAC + ACK + AKC = 180°
=> ACK = 40°
Mà IHK + IHC = 180° ( kề bù)
=> KHI = 130°