As shown in the figure: the straight lines a and B are perpendicular to the straight line L, and ∠ 1 = (2x) °, ∠ 2 = (3x + y) °, ∠ 3 = (2 & nbsp; Y-X) °, then the degree of ∠ 1 is______ .

As shown in the figure: the straight lines a and B are perpendicular to the straight line L, and ∠ 1 = (2x) °, ∠ 2 = (3x + y) °, ∠ 3 = (2 & nbsp; Y-X) °, then the degree of ∠ 1 is______ .

∵ straight lines a and B are perpendicular to the straight line L, ∥ a ∥ B, ∥ 2 = ∥ 3, ∥ 1 + ∥ 2 = 180 °, ∥ 3x + y = 2Y − X2X + 3x + y = 180, the solution is x = 20, ∥ 1 degree is 40 °