solve the equation 18 = - 2 / 3 m

elijah said:
18=-2/3m
Click to expand...

If you do not show your work, then how can we possibly know where you got stuck?

Anyway, we have 18 = -2/3m

We want to remove the fraction on the right side of this equation as step one.

To do so, multiply both sides by 3m.

(3m)(18) = (-2/3m)(3m)

54m = -2

To find the value of m, we now apply the division rule of equality, which tells us to divide both side of the equation by the coefficient of m or 54.

After doing so, we get this:

m = -2/54

Can we reduce -2/54 to the lowest term?

Yes, we can.

Divide the top and bottom by -2.

After doing so, we get this:

m = -1/27

How do I know that this is the right answer?

====================================

THE PROVE:

Let m = -1/27 in the original equation given.

If I get the same answer on both sides, then I will know that m = -1/27 is right.

You were given:

18 = -2/3m

Replace m with -1/27 and simplify.

18 = -2/3(-1/27)

18 = -2/(-1/9)

18 = -2 times -9

18 = 18...IT CHECKS!!!

So, the final answer is m = -1/27

Is this clear?

===========================

Now, if you meant to type 18 = -2m/3, then this is how it's done.

Multiply both sides by 3. This is done to clear the fractions.

3(18) = (-2m/3) (3) The (3) in red is actually (3/1).

=================================================

54 = -2m

54/-2 = m

-27 = m

================================================

THE PROVE:

18 = -2(-27)/3

18 = 54/3

18 = 18...It checks!

Thus, m = -27
 
elijah said:
solve the equation 18 = -2/3 m
Click to expand...


First, learn how to do arithmetic with fractions.

Then, multiply both sides of the equation by the reciprocal -3/2.

 
There seems to be some confusion as to what the original posting meant.

According to the Order of Operations Convention, 18=-2/3m means \(\displaystyle 18=-\frac{2}{3}m\).

To have the m in the denominator one needs to post as 18=-2/(3m). getting \(\displaystyle 18=-\frac{2}{3m}\).
 
Loren said:
There seems to be some confusion as to what the original posting meant.

According to the Order of Operations Convention, 18=-2/3m means \(\displaystyle 18=-\frac{2}{3}m\).

To have the m in the denominator one needs to post as 18=-2/(3m). getting \(\displaystyle 18=-\frac{2}{3m}\).
Click to expand...


True but maybe the student does not know how to use parentheses and brackets correctly.
I thought he or she meant 18 = -2/(3m).

If the actual case is 18 = (-2/3)(m), which can also be written 18 = -2m/3, then it is done another way.
 
Now, if you meant to type 18 = -2m/3, then this is how it's done.

Multiply both sides by 3. This is done to clear the fractions.

3(18) = (-2m/3)(3)

54 = -2m

54/-2 = m

-27 = m

THE PROVE:

18 = -2(-27)/3

18 = 54/3

18 = 18...It checks!

Thus, m = -27
 
Awwrrighty then! It has only taken us 24 million lines to do what Mark mmm showed could be done in two. Thanks for your time, in helping to solve a problem in which the original poster showed no initiative since Nov. 20. :)

"Give a man a fish, and he'll be hungry the next day. Teach a man to fish, and he'll be able to feed his family for life."

Sorry to be so sexist in my choice of maxim, but to the original poster, if you have ever looked at this problem again (I doubt it, but you never know), let me reiterate the best advice yet, given above by Subhotash:

In the meantime you may want to review at:
http://www.purplemath.com/modules/solvelin.htm

That you can take to the bank and beyond. The purplemath site is run by one of the moderators on this help board. There, you will find clear instructions about how to solve problems like this one, and I have seen, many more in the years to come.

-Paul
 
Thassa shore good PAULitics, Paul :wink:

I often wonder why answers are sometimes posted to a thread
that's been "dead" for a while...really a waste of time...
 
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