What is the simplifying process of
0.08r+0.5(x+100)=73.2
First multiply out the parentheses term.
0.08r + 0.5x + 50 = 73.2
0.08r + 0.5x = 23.2
You could also write that as
0.16r + x = 46.4
or
8r + 50x = 2320
It is not clear what they consider the simplest form.