If the image of the first-order function y = KX + B and the image of the function y = 1 / 2 x + 1 are symmetric about the Y axis, then the expression of the first-order function is?

If the image of the first-order function y = KX + B and the image of the function y = 1 / 2 x + 1 are symmetric about the Y axis, then the expression of the first-order function is?

Two functions and images are symmetric about the Y axis,
The analytic formula can be obtained by directly substituting - x for X,
Y=1/2(-X)+1
That is y = - 1 / 2x + 1