Chapter 8.4, Problem 11MC

Janis noticed that in the simultaneous equations

$\begin{array}{l}2x-3y-5=0\\ 4x+6y+10=0\end{array}$

$\frac{2}{4}=\frac{3}{6}=\frac{5}{10}$ and the system has infinitely many solutions. She would like know whether, if a similar situation occurs in other systems of two equations in two unknowns, the corresponding system will have infinitely many solutions. How do you respond?