Ok so lets start off with calculating the percentage. We have 240 cards so lets find 25% of them so lets use 240 times .25 we get 60 cards then take away 240 - 60 = 180. Next we do the 30% so 240 times .30 would be 72 so take away 180 from 72 thats 108. So there are 108 Houston Astros Cards.
If by description you mean simplification then: 84x/28
A binomial squared is written like

So, we have 
So, we want to complete the square 
We can add and subtract 9 to write
