For each of these three equations, determine whether there are any solution(s). If there are solutions, say what they are and show how you found them. If there aren't solutions, explain why not. (a) $\textcolor{white}.~~\frac x3+\frac x4+\frac x5 ~=~ \frac{2x}3 + \frac{2x}4 + \frac{2x}5$

(b) $\textcolor{white}.~~\frac y3+\frac y4+\frac y5 ~=~ \frac y3+\frac y4+\frac y5+1$

(c) $\textcolor{white}.~~\frac z3+\frac z4+\frac z5 ~=~ \frac z4+\frac z5+\frac z6+1$