I'm using the kimmel asterisk method to factor 3x^2-21x+15. the method gives me (x-1)(2x-5), but that is incorrect because that answer is missing a factor of 3. Can anyone tell why the asterisk method isn't giving the correct answer?

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anonymous · Answer

i just looked at this method,sounds very time consuming.But anyway you should first factor out the 3 before applying this method

anonymous · Answer

I couldn't find in any math reference that you should factor coefficients first. The kimmel asterisk method is being taught in today's middle and high schools. I'm tutoring one of them, I personally don't like the method, but they are teaching it. Thank you for helping out.

anonymous · Answer

i looked it up in youtube and the teacher started by factoring the common factor out then she applied the star thing http://www.youtube.com/watch?v=HEb4nYv4mbU