Re: Simple Question, Don't Make Fun Please:)
- From: stush@xxxxxxxxxxxxxx
- Date: 23 Jun 2006 12:32:22 -0700
Pious Audio wrote:
I posted here a couple of weeks ago and said I was going to start
working on my math, as I've managed to get through grade school, high
school and a four-year degree without properly learning anything about
the subject. Anyway, I've purchased Morris Kline's "Mathematics for
the Nonmathematician" and am working through it's chapters and
understanding most concepts well. However, I've come accross this
issue which I can't comprehend:
The problem is presented as (3x + 4) (x + 5), and I'm supposed to
transform this to an equal expression. I've used the distributive
property and got 3x^2 + 15x + 4x +20, and then combined those to 3x^2 +
19x + 20, which I've checked against the back of the book and it says
that's the correct answer.
What I don't understand is why we stop at 3x^2 + 19x + 20. Couldn't
the x's be combined
(3x^3 + 19 + 20) so that the 19 and 20 could be added, leaving 3x^3 +
39? I missed a concept somewhere.
I'd appreciate your help!
You are on the write track using the distribute property.
Write it out...
15x + 4x = 19x because
15x + 4x = (15+4)x // dist. prop
But
3x^2 + 19x <> 3x3 + 19 because
3xx + 19x = (3x+19)x // dist. prop
.
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- From: Pious Audio
- Simple Question, Don't Make Fun Please:)
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