See explanation below
Explanation:The coordinates of triangle RST: R(7,4), S(5,-3), and T(2,6)
A reflection across the y = x means (x, y) becomes (y, x)
[tex]\begin{gathered} \text{Arrrow rule for transformation:} \\ (x,\text{ y)}\rightarrow(y,x) \end{gathered}[/tex]Plotting the graph of the original image:
After the reflection aross the line y = x, the new coordiantes will be:
R'(4, 7), S(-3, 5) and (T(6, 2)
plotting the graph of the image:
Both the original and new image: