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### Pre-Algebra problem

Date: Fri, 11 Nov 1994 11:03:41 -0700 (MST)
From: John Murgel
Subject: pre-algebra

I am a teacher and would like to run this by you guys. Here is the
student?

-3n + 65 = -40 - 7n

My math count students will be working problems such as this in their
state contest.

Date: Fri, 11 Nov 1994 16:55:59 -0500 (EST)
From: "Michael W. S. Morton"
Subject: Re: pre-algebra

Hey there!

I'm one of the Math Doctors here.  I'll show you what I'd do to
try to help out a 7th grader, and maybe some of the other math
doctors have other ideas.

>   -3n + 65 = -40 - 7n

n + 5 = 12

then ask what numbers would work there? (7).  Ask how the student
came up with that answer.  Then explain it in this way:

n + 5 = 12

subtract 5 from both sides of the equation:

n + 5 - 5 = 12 -5
n = 7

If subtracting a number from both sides of the equation is not clear
to a student, try saying:

1 = 1
does    1 - 5 = 1 - 5 ??

Since n represents a number ( a real, physical number) we can add
or subtract a real number to both sides and not change anything.

So, moving on....

Then say:
2n + 5 = 13
2n + 5 - 5 = 13 - 5
2n = 8
n = 4

This should be relatively clear.
You can go from there...

As I'm typing this, I'm thinking this is not quite what you wanted to
know (or wanted to hear)  If it is not, PLEASE write us back, and
we'll try to help you out some more.  Sorry if this is over-simplified
or not what you wanted; just write back and let us know!

-MORTON, Doctor of sorts

Associated Topics:
Middle School Equations

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