mathematical problem [simultanious equation]

hi all ive run myself into a slight problem my professor says i should turn my problem into a simultanious equation, but i have no idea how ( applied to do a network engineering course, got stuck doing electronics in first year) basically i cannot work out what ID or VGS are, he says turn into a simultanious equation and work it.. but i have no idea how to do that so im running here for guidance on how to solve this equation but the most important thing on how one came to solve the problem step by step, so then i can understand on how to solve it.

ive attached a document because i cant write the equation in here without it being confusing.


Cheers!
Skye

For simplification purposes, lets refer to Vgs as V, and ID as d

So, you have 2 equations:

V = 2.785-d
d = 8*[(1+(V/4))²]

So, if you substitute the first equation into the second, {substitute 2.785 - d for V}, then square the term, you'll have a single order 2 equation with d as the variable.

All you then would have to do is apply the quadratic equation to determine d.

At work, so I can't expand on it at this time.

:)
-Lou

[edit] lol, it looks easier if you substitute the second equation into the first, then square, and solve for V. Either way. Have fun!

:wave: