What? There is no such thing as an "implied agreement"
Yes there is, and it is fundamental to commercial law.
Classic example: you walk into a store and pick up a carton labeled "milk". You hand the clerk the price printed on the box, and leave.
There is an implied contract of sale even though you signed nothing, and it is a fairly complex contract that gets loaded up with many default terms and conditions binding both parties.
For example, you have a contractual expectation that the carton contains milk, that it is safe to drink, and that it contains the percentage of fat printed on the label.
Even if you didn't get a receipt the implied contract has terms and conditions around the price you paid, how much it is, including how much is tax, and including the expectation that you pay in full. If it turns out that unknown to you, one of your bills is counterfeit, that implied contract compels you to return and pay balance owing, even though the clerk unknowingly accepted the fake money and you left. The implied contract of sale assumes the posted price and requires you to pay, regardless of the amount you put on the counter.
That is an implied agreement. They can be simple or complex but they certainly do exist and they are created by you many times a day as you go about your ordinary activities.