Its a reflection over an x-axis, whats "positive" goes "negative" and whats "negative" goes "positive" with respect to y.
If a shape [tex]S[/tex] is a subset (made of [tex]P_2\cup P_3[/tex] of quadrants [tex]Q_2,Q_3[/tex] then the part [tex]P_2[/tex] that lies in the second quadrant gets mapped to [tex]Q_3[/tex] and part [tex]P_3[/tex] that lies in third quadrant gets mapped to [tex]Q_2[/tex]
Hope this helps.
