A clockwise rotation is given by:
[tex]\begin{gathered} x^{\prime}=x\cos (\theta)+y\sin (\theta) \\ y^{\prime}=-x\sin (\theta)+y\cos (\theta) \end{gathered}[/tex]
so:
[tex]\begin{gathered} x^{\prime}=x\cos (180)+y\sin (180)=-x \\ y^{\prime}=-x\sin (\theta)+y\cos (\theta)=-y \end{gathered}[/tex]
Therefore:
[tex]\begin{gathered} A(2,2)\to(-x,-y)\to A^{\prime}(-2,-2) \\ B(3,-2)\to(-x,-y)\to B^{\prime}(-3,2) \\ C(-1,3)\to(-x,-y)\to C^{\prime}(1,-3) \end{gathered}[/tex]
