Question 1165294
<pre>
The other tutor above made a mistake, so her answer is wrong.  She may
come back and correct it.  I will check back later to see if she corrects
it.  If she does I'll erase this notice.  Anyway here's the correct way to
approach the problem:

{{{matrix(1,9,

(matrix(7,1,The, number, of, minutes, in, an, hour)),
"",
"",
(matrix(4,1,is, the, same, as)), 
"",
"",
(matrix(4,1,a, number, times, three)),
(minus),
(3) )}}}

In place of "The number of minutes in an hour", write 60.

In place of "is the same as", write an equal sign, = .

In place of "a number times 3, write 3x .

In place of "minus", write a minus sign, - .

So you should have this:

        60 = 3x - 3

We want to get all terms containing x on one side.  Since the only term
containing x is 3x, we'll leave it on the right side.

We want to get rid of the -3, so we'll add its opposite, +3, to BOTH sides,
like below, so that the +3 will cancel out with the -3. We add the 60 and
the +3, we bring down the equal sign and the 3x. We leave it blank where
the -3 and the +3 cancel out.

        60 = 3x - 3
        +3       +3
     ----------------
        63 = 3x  

Now that we have only one x term on one side and only one term with no x on
the other, we are ready to divide both sides by the coefficient of x.
That's the number that is multiplied by the x, which is 3.  We draw a
fraction bar under the terms on both sides like below, and put a 3 under
both of them:

       {{{63/3 = 3x/3}}}

Now we divide 63 by 3 and get 21 on the left, and we cancel the 3's on the
right.

       {{{21 = cross(3)x/cross(3)}}}

And we just write:

       {{{21 = x}}}

Or if we prefer we can swap sides so that x comes first.

        {{{x = 21}}}

Edwin</pre>