we know that
In a Rhombus all sides are congruent
so
[tex]MJ=JK=KL=ML[/tex]
we have
[tex]MJ=3x\ units\\JK=(2x+4)\ units[/tex]
equate MJ and JK
[tex]3x=2x+4[/tex]
Solve for x
[tex]3x-2x=4[/tex]
[tex]x=4\ units[/tex]
Find the length side of the rhombus
[tex]MJ=3x[/tex]
[tex]MJ=3*4=12\ units[/tex]
therefore
the answer is
The length side of the rhombus is [tex]12\ units[/tex]
