63-x=180° Calculate angle X.

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 60°+51°+3a=180°

3a=180°-111°=69°

a=23

Then,

a+40°+x=180°

23°+40+x=180°

63-x=180°

x=180°-63=117°✓

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X=52

Y=128

Z=52

X=Zللتقابل بالراس

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