Question 250097
This says to collect like terms and I'm totally lost can you all help?
<pre><font size = 4><b> 
I'll do some coloring:

<font color = "red">12r</font><font color = "blue">+4s</font><font color = "red">-6r</font><font color = "blue">-6s</font>=?


The two <font color = "red">red</font> terms are like terms because they have the same letter <font color = "red">r</font>.
They don't have the same coefficient, but they have the same letter,
so they are considered like terms and they can be combined.

The two <font color = "blue">blue</font> terms are like terms because they have the same letter <font color = "blue">s</font>. 
They also don't have the same coefficient, but they have the same letter, 
so they are considered like terms and they can be combined.

To keep things straight, sometimes people rearrange the terms first
so that they will be together, like this, where I have swapped the middle
two terms:

<font color = "red">12r-6r</font><font color = "blue">+4s-6s</font>?

Then to combine the two <font color = "red">red</font> terms, we just combine their coefficients
<font color = "red">12-6</font> getting <font color = "red">6</font> and then put on the <font color = "red">r</font>, getting <font color = "red">6r</font>.

To combine the two <font color = "blue">blue</font> terms, we similarly combine their coefficients 
<font color = "blue">+4-6</font> getting <font color = "blue">-2</font> and then put on the <font color = "blue">s</font>, getting <font color = "blue">-2s</font>.

So the final answer is <font color = "red">6r</font><font color = "blue">-2s</font>

Edwin</pre>