Answer:
MN ≈ 92.1
Explanation:
given the figures are similar then the ratios of corresponding sides are in proportion, that is
 =
 = 
 ( substitute values )
 ( substitute values )
 =
 = 
 ( cross- multiply )
 ( cross- multiply )
13 MN = 21 × 57 = 1197 ( divide both sides by 13 )
MN ≈ 92.1 ( to the nearest tenth )