Given that, ∠x = 45°
From the figure we can write as
∠x = ∠z = 45°
Also from the figure, we have
∠y = ∠u
From the property of linear pair we can write as
∠x + ∠y + ∠z + ∠u = 360°
45° + 45° + ∠y + ∠u = 360°
90° + ∠y + ∠u = 360°
∠y + ∠u = 360° – 90°
∠y + ∠u = 270°
∠y + ∠z = 270°
2∠z = 270°
∠z = 135°
Therefore, ∠y = ∠u = 135°
So, ∠x = 45°, ∠y = 135°, ∠z = 45° and ∠u = 135°