TW is the midsegment of the trapezoid UVXY
=> 2TW = XY + UV
=> 2(z - 2) = 4z - 34 + z
=> 2z - 4 = 5z - 34
=> 5z - 2z = 34 - 4
=> 3z = 30
=> z = 10
Answer: z = 10
Ok done. Thank to me :>
