Question

abcd is parallelogram in which ab=9cm and the perimeter is 30cm find the length of each side?

Answer 1

AB=9
CD=9 (opposite sides of a parallelogram are equal)
LET  X BE THE ADJACENT SIDE
X+X+18=30
2X=30-18
2X=12
X=6
BC=6
AD=6
I HOPE THIS HELPED U.. 

Answer 2

AB=CD ( OPPOSITE SIDES )
9 CM=9 CM.
AND THE OTHER TWO SIDES ARE ALSO EQUAL .( DA=BC )
LET DA=BC=a
THEN,
         AB+BC+CD+DC=30
         9+9+a+a=30
         18+2a=30
         2a=30-18
         2a=12
         a=12/2
         a=6 
∴DA=BC=6 CM.
      i hope that this will help u.