How do I solve reflection across the line y=2 ?

Question

I don't understand how to solve ' reflection across the line y=2'

Answer 1

you have a mirror image of the original figure

the x-values of the mirror image will stay the same

look at the y-values

the y-values must be the same number of units below the line y=2 as above the line y=2

for example, if a y-value is 2 units above the line y=2, the mirror image of that y-value must be 2 units below the line y=2

(x--->x, y--->-y+4) in algebraic terms