Answer:
The value of  x  = 5 and y = 2.
Step-by-step explanation:
Here, given DECK is a parallelogram.
Also, KT = 2x + y  , DT = x + 2y  , TE = 12   and TC = 9
Now, in parallelogram: 
DIAGONALS IN A PARALLELOGRAM BISECT EACH OTHER
Also, in the parallelogram DECK, 
Sides DC and KE are two diagonals.
⇒ T is the mid point of AC and KE.
⇒ KT = TE and DT = TC ( as diagonals are bisected)
⇒  2 x +   y =  12 and x  +  2y = 9
So here, the set of two equations are:
 2 x +   y = 12  ....... (1)
 x  +  2 y = 9  ....... (2)
Multiply (2) with -2 and add with (1), we get:
2 x +  y  - 2 x - 4 y = 12  - 18
or, - 3 y = - 6
or, y = 2
If y = 2, then x  +  2 (2) = 9 or, x  = 5
Hence the values of  x  = 5, y = 2