Answer:
x = 8/3
y = 7/3
Explanation:
In a parallelogram the diagonals bisect each other.
So 2x = y + 3
x + y = 5
Then you set them up to do combination/elimination to solve for the two variables.
2x-y = 3
Then you add the two equations together
3x = 8
Solve for x
x = 8/3
Then solve for y by plugging it into a equation
x + y = 5
8/3 + y = 5
8/3 - 5 = -y
8/3 - 15/3 = -y
-7/3 = -y
y = 7/3