The transformation is a reflection in the line
![y=x](https://img.qammunity.org/2019/formulas/mathematics/middle-school/4h9lrf0zk1zd2kr0hgvek2yvdc933wshqp.png)
followed by a reflection in the line
![x=1](https://img.qammunity.org/2019/formulas/mathematics/middle-school/etd77jui6mm2z2ngebg2jbgevvrgge83wx.png)
.
The mapping for a reflection in the line
![y=x](https://img.qammunity.org/2019/formulas/mathematics/middle-school/4h9lrf0zk1zd2kr0hgvek2yvdc933wshqp.png)
is
![(x,y) \rightarrow (y,x)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/qyttw4o6uj3hejmup0717nq52f4blqdwuh.png)
.
That is simply swapping the coordinates.
Now we reflect the resulting coordinates in the line
![x=1](https://img.qammunity.org/2019/formulas/mathematics/middle-school/etd77jui6mm2z2ngebg2jbgevvrgge83wx.png)
which has the mapping
So we transform the resulting coordinates as follows:
Hence we have
![A'(-2,-3),B'(2,-3) \: and\: C'(-1,-1)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/cjkfwqjjqz6yyfzwj1rqaeyjqs9u0ofmm8.png)