Answer:
Given the statement: BE = 2x + 6 units and ED = 5x - 12 units.
By properties of parallelogram:
The parallelogram bisects each other at E.
You can see the diagram of parallelogram as shown below.
Therefore;
.....[1]
Substitute the given values we have;

Add 12 both sides we get;

Subtract 2x from both sides we have;

Divide 3 both sides we get;
x = 6.
BE = 2x+6 = 2(6)+6 = 12 +6 = 18 units
We have to find the value of BD:
BD = BE+ED
from [1] we have;


Therefore, the value of BD is, 36 units.