Answer:

Step-by-step explanation:
we know that
In a parallelogram opposite sides are congruent
In this problem
we have that
AB and DC are opposite sides
AD and BC are opposite sides
so
AB=DC
AD=BC
step 1
Find the value of x
AB=DC
substitute the given values

solve for x



step 2
Find the length of AD
we have that

substitute the value of x

step 3
Find the length of BC
Remember that
AD=BC ----> by opposite sides
therefore

Answer:
2/5m - 1/5
Step-by-step explanation:
2(1/5m - 2/5) + 3/5
= 2/5m - 4/5 + 3/5
= 2/5m - 1/5