TRiangles ABC and AUV are similar so their corresponding sides are in the same proportion.
Therefore AU / AB = AV / AC
AB = AU + UB = = 20x + 108 + 273
= 20x + 381
So 20x + 108 / 20x + 381 = 372 / 589
Cross multiply:-
589( 20x + 108) = 372(20x + 381)
11780x + 63612 = 7440x + 141732
4340x = 78120
x = 78120/4340
x = 18 answer