Answer:
5
Step-by-step explanation:
Given that:
JK = 5x, ML = 4x+1
A rhombus is also called an equilateral quadrilateral since all of its sides are equal in length.
So, the length of all four sides of the given rhombus are same. Thus, JK = L.

Length of one side of rhombus = 5(1) = 5
Since KL is a side of the rhombus and all sides have the same length, KL= 5.