# I can't get this stupid equation right! [solved]

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I've got this equation, .6x^2 + 1.8x + 0 = 0. I need to turn it into the form (ax - b)(cx - d) = 0. I used the quadratic formula to find the roots, which are 3 and 0. However, (x+3)(x+0) does not quite produce the same graph as .6x^2 + 1.8x + 0, and I don't understand why. I maybe should have waited to start this calculator project thing I'm working on until after I finished calculus, but as it is, I'm stuck. Any help? [Edited by - silverphyre673 on October 20, 2005 7:47:26 PM]

wendigo23    512
Factor out 0.6x.

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LilBudyWizer    491
Because x*0=0. So you can multiply both sides of the equation by a constant and not change the roots. So 0.6*x*(x+3) has the same roots as x*(x+3) although they are differant curves.

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Quote:
 Original post by LilBudyWizerBecause x*0=0. So you can multiply both sides of the equation by a constant and not change the roots. So 0.6*x*(x+3) has the same roots as x*(x+3) although they are differant curves.

Oh, OK. So then, I guess I'm not going about this correctly. From an original equation of

.6x^2 - 5.4

I used synthetic division to get the equation

.6x^2 + 1.8x

Now I need to convert it to (ax + b)(cx + d) form. I thought that you just found the roots of the above equation, but I think this is where I'm going wrong. Can anyone provide an explanation of where I'm going wrong? I had this a couple of days ago, but I think the process has slipped my mind somewhere along the way.

EDIT: Wait a second, .6(x + 3)(x) gives the same graph as .6x^2 + 1.8x. I think I understand now. Thanks!