Samatha has pens and pencils which together are 40 in number. If she has five more pencils and five less pens, then number of pencils would become four times the number of pens. Find the original number of each.

Question

terenzreignz · Answer

It helps to represent.
If we let x= number of pencils, how would you represent the number of pens?

anonymous · Answer

It's linear equations in two variables, so the no. of pens would be y...

terenzreignz · Answer

Well, all right, that could work. 
So, to solve for x and y, you need to equations that have these variables.  Can you find them?

terenzreignz · Answer

you need *two* equations... gah

anonymous · Answer

That's the problem... I can't form the equations....

terenzreignz · Answer

No fear, Terence is here :D
But seriously, let's work it out together :D

"Samantha has pens and pencils which together are 40 in number"

What does that tell you about x and y?

terenzreignz · Answer

Ok, specifically, what does that tell you about x + y ?