Answer:
R=(-1,2), T=(-7,4) S=(-2,8)
Step-by-step explanation:
The line y=x is a diagonal line veering to the left, since I can't draw it I'll give you a link on an actual digram of a triangle getting reflect across y=x. But, I just like to do this, if for example Q=(10,-3), I just exhange the negative sign to the left, so it would equal Q"=(-10,3) (Q" means the new modified Q).
The link thingy=https://www.quora.com/What-does-it-mean-to-reflect-over-the-y-x-line
Hopes this helps (:
