No 28-29 plisss donk...buat bsok mtk ukk ....

< BAC = 180- (X +50) = 130 -X 
<  ABC = 45
<CAB = 180 -( 2x-50) = 230 -2x 

< BAC + <ABC+<CAB = 180
(130-x) +45+(230-2x) =180
405-3x =180
x = 75

<BAC = 130 - x = 130-75 =55