Do you mean:     y = 15 , 418  e ^(-0.929x)    ???         you'll need more info to calculate 'y' or 'x'     

e is a mathematical constant, approximately 2.71828

👀👀

It is easier to write e than 2.71828 😜

👉 Your calculator probably has this number already stored in it, look for the e button. A scientific calculator has a button with the power function, e to-the-power x, and it's this button you can use to calculate y in your formula once you know a value for x.

Badinage