The cost of 3 boxes of envelopes and 4 boxes of notebook paper is $13.25. two boxes of envelopes and 6 boxes of notebook paper cost $17. find the cost of each.

There were 816 people at a concert when a band started to play. after each song, only half the people stayed to hear the next song. how many people were left at the concert after x songs? write a function to represent this scenario.

What expression is equivalent to 42x-56y

Intro biblioteca sunt 462 de carti cu 198 mai putine enciclipedii si cu 47 mai multe dictionare decat enciclopedii cate enciclopedii sunt in biblioteca