arranging for quadratic equation

[Ryan222]

This equation is giving me a lot of trouble. I cannot rearrange it properly into the form ax^2 + bx + c = 0.

Don't know if it matters, but the rearranging is for Shockley's Equation for Junction field-effect transistors (JFETs).

The equation is:

-x/470 = 0.008 (1-(x/-4))^2

It was done in class but I can not get it myself.

Thanks for any help,

Ryan

 

[galactus]

Expand out and you can see it.

\(\displaystyle \L\\\frac{1}{125}(1+\frac{x}{4})^{2}+\frac{x}{470}=0\)

\(\displaystyle \L\\\frac{1}{125}(\frac{x^{2}}{16}+\frac{x}{2}+1)+\frac{x}{470}=0\)

Can you finish it?.

 

[Ryan222]

x^2/2000 + (x/250 + x/470) + 1/125 = 0

roots are -1.488 and -10.752 (what we arrived at in class)

I think I got it,

Thanks a lot!

Ryan