Question 1036105
Here's my question:
Pearly and Peggy Sue left their dorm room at the same time and headed in opposite directions.  After 9 hours, they were 1,080 miles apart.  If Pearly drove 20mph faster than Peggy Sue, how fast did Peggy Sue drive?

I think the formula is {{{ 9x+(9x+20)=1,080 }}}  Is this right?  If not, how do I do it?
<pre>How did you get 9x? Isn't that the DISTANCE (times * speed) traveled by Peggy in 9 hours?
How did I get 9(x + 20)? Isn't that the DISTANCE (times * speed) traveled by Pearly in 9 hours?
When you add these 2 distances (Peggy's and Pearly's), what should they total? Shouldn't the 2 distances sum to the distance they are apart? Of course!! 
Therefore, you should get: {{{highlight_green(9x + 9(x + 20) = matrix(1,1, "1,080"))}}}, instead of 9x + (9x + 20) = 1