Why does current divider rule use negative sign if current direction is opposite?

Hi guys, there's something confusing me on the equation/rule of current divider, what's confusing me is this:if I have direction of current is opposite to what's the equation required, so why I use ( - ) the current that I assigned?On this link there's a photo of circuit satisfying current divider:https://en.wikipedia.org/wiki/Current_divider#/media/File:Low_pass_RC_filter.PNG
so why if I put the direction IC from bottom to above (opposite to what's shown on the photo), as why I need to assign it as (-Ic) and not IC on the equation?if I use (-Ic) I know it's because I direct my current opposite to what the equation required, but on the circuit found Ic, and not -Ic so once assigning -Ic we totally change the circuit's current and not the same our current that's found on the circuit ... so how's really current divider give me the right answer even though my current is opposite?!

Ryan,
I think you have skipped some steps in your reading and that has led to your confusion. So before I try to answer your question, I'd like to make sure you understand the basics.

Start with this tutorial https://www.electronics-tutorials.ws/dccircuits/dcp_1.html
once you understand this one, then go on to the next one in the series. This series starts out really basic but each one builds on the previous one so it's important that you understand each one before you go on to the next. The first few should be mostly review but don't skip to the next unless you are sure you understand what you are reading about.
Once you understand Kirchoff's Current Law and Kirchoff's Voltage Law, you will be in a better position to understand the answer to your question.

Ryan:a) Your question makes no senseb) although there is an equation in the Wikipedia reference you give, it does not have -Ic in it.c) Please show all your workings thus far before anyone here spends anymore time on this

Ryan -- I've asked you these questions before -- to better help you, can you tell us:a) Your age
b) The name of the institution you are attending (school, college, university)c) The names of the course or courses are you taking

I replied before !
1) 21 years old (turning to 22)2)not attending3) learning by myself to work as a analog designer