Equations written in symbols

[Linda]

I have an equation written in symbols similar to those used in Europe in 1631. How would we write this equation today?

aaaa - 4bba= +3.ccc (the plus sign is really smaller and up higher next to the 3)

Any help would be greatly appreciated.

 

[Quaid]

Different authors from that time used the same notation to mean different things. For example,

y = ddx

The 'dd' could be implied multiplication of a constant (represented by d) times itself; in other words, dd=d^2. Or, it could denote a two-dimensional object, not necessarily a square.

I'm not sure about the superscript plus-sign or that lone dot.