what is x equals - b plus or minus radical b squared plus 4 times a times c all above 2 times a.

That's the quadratic formula. You use it to solve a quadratic. ax^{2}+bx+c=0

For instance, x=\frac{-b\pm\sqrt{b^{2}-4ac}}{2a}

Suppose you have x^{2}+3x-2=0

You have a=1, b=3, c=-2. Plug them into the formula and find your solutions.

There seems to be a typo in Kenny's posting - he has "plus times a times c," whereas the quadratic formula has minus 4ac. Either that or the equation his version solves is:


ax^2 + bx - c = 0

Good catch, ebaines. I'm thinking, perhaps, it's a typo.

I think it is a typo of his, NO PERHAPS. ;)