Question 285345
{{{ x^2 + 6x + 8 = 0 }}} is a <b>quadratic equation</b>, so use the 
formula {{{ax^2+bx+c=0}}} <br>
in this case we have:
a = 1
b = 6
c = 8

{{{ x[1,2] = (b+-sqrt( b^2-4ac ))/2a }}}
Notice that you will have <b>two answers!</b>
*[invoke quadratic "x", 1, 6, 8]<br>
Quadratics have always been one of my favorite equations, because they are <i>so much easier</i> than factoring!

Go through the quadratic explanation above several times. Once you think you understand it, use some different numbers and see if you can calculate it out to the same answer the computer gives you until you're sure that you understand it. It will save you <b>massive</b> amounts of work in the future! 

Once you understand the quadratic, bob's your uncle!