SOLUTION
For
[tex]\begin{gathered} R_{270^o}\text{ Counter clockwise } \\ (x,y)\rightarrow(y,-x) \\ \text{This means that (-4, 6) }\rightarrow\text{ (6, 4)} \\ \text{For r}_{y=x}\text{ on (6, 4)} \\ (x,y)\rightarrow(y,x) \\ \text{Therefore, r}_{y=x}\text{ on (6, 4) becomes (4, 6)} \\ \end{gathered}[/tex]
So our answer is (4, 6)
