The inclination angle of the line L1 is 120 ° if the line L2 and L1 are symmetrical about the X axis, then the inclination angle of the line L2 is - the slope is——

The inclination angle of the line L1 is 120 ° if the line L2 and L1 are symmetrical about the X axis, then the inclination angle of the line L2 is - the slope is——

60° √3

(Anhui, 2004) it is known that the line L: x-y-1 = 0, L1: 2x-y-2 = 0. If the line L2 and L1 are symmetric with respect to L, then the equation of L2 is ()
A. x-2y+1=0B. x-2y-1=0C. x+y-1=0D. x+2y-1=0

The intersection point (1,0) of the line L: x-y-1 = 0, L1: 2x-y-2 = 0. Substituting the option, we can see that a is incorrect; the slope of the line L is 1, and the slope of the line L1 is 2, so the slope of the line L2 ∈ (0,1), obviously C and D are incorrect; so we choose B