Find the value of x and y

x = 33, y = 81

You can see that the two lateral and vertical sides of the quadrilateral are congruent respectively, meaning that ∠3x = ∠(2x+33).

You also know that 3x + y = 180° since they're supplementary.

To solve for x, just solve the equation I wrote above:

3x = (2x+33)    (subtract 2x from both sides, and that automatically gives you

x = 33               the value)

To solve for y, plug it into the second equation I provided:

3(33) + y = 180

99 + y = 180

y = 81

∴ x = 33, y = 81

thats not a system of equations, that is a solution