Answer:
see explanation
Step-by-step explanation:
If a parallelogram then AB = DC and AD = BC
Equating AB = DC, then
3x = x + 4 ( subtract x from both sides )
2x = 4 ( divide both sides by 2 )
x = 2
Thus
AB = 3x = 3(2) = 6 and DC = x + 4 = 2 + 4 = 6 ⇒ AB = DC
Equating AD and BC, then
2y = y + 2 ( subtract y from both sides )
y = 2
Thus AD = y + 2 = 2 + 2 = 4 and BC = 2y = 2(2) = 4 ⇒ AD = BC
Since opposite sides are congruent then ABCD is a parallelogram
