Pls help me with this

Step-by-step explanation:
a)
clearly, A and B are mirrored images of each other around the x-axis.
and the equation of the x-axis is simply
y = 0
b)
this is trickier.
first of all, the mirror line is now vertical and not horizontal.
and where is it ? of course, in the middle between A and B.
how many units are there between A and B ?
I am counting 5. so, the middle between them is 2.5 units.
so, let's go e.g. from A 2.5 units to the right (in the direction of B).
where do we end up ? at x = 0.5
and that is also the equation of the vertical line there.
again
x = 0.5