I got the Roots R=5,2 for y''-7y'+10y=0
So the equation would be y=C1e^5x +C2e^2x
and not y=C1e^2x+C2e^5x OR Does It even matter where you stick the roots????
You can try it out both ways and see that you'll get the same thing if it was or
However, note that and values you will get from solving it both ways will be different, but you will see that they correspond to the same term.