Okay, here we have this:
Considering the provided information, we are going to calculate how much more is a burger meal than a chicken meal, so we obtain the following:
Then from the given information we obtain the following system of equations, where x represents the price of hamburgers and the price of chicken dishes:

So we'll isolate x in the first equation and replace it with it in the second:

Replacing:


Finally we obtain that a hamburger is: $9.6-$7.55=$2.05 more expensive than a chicken meal.