
Re: Please help refresh my Algebra skills (factoring & solving)
Posted:
Oct 17, 1999 5:50 PM


On Sun, 17 Oct 1999 15:06:40 0400, "Nick Marques" <nickjm@jnlk.com> wrote:
>If I have some nasty numbers in quadratic form, how do I factor and solve >for the TWO answers?? > >4.9x^2+5.5x105=0 >That factors to x(4.9x+5.5) = 105
Gets you nowhere. You are looking for two factors of the form (Ax+B)(Cx+D). The + might be . However, MUCH easier to use the quadratic formula, especially in this case as you will see.
Start with positive x^2 (why not?)
4.9x^2  5.5x + 105 = 0
Use the formula:
x = (b +sqrt(b^24ac)/2a to get
x = (5.5 +sqrt((5.5)^2  4*4.9*105))/(2*4.9)
Out with the calculator, and it looks like they might be complex roots.
Dan.

