Hello there,
This problem is on my math homework tonight, and I'm so confused.
I tried to work on it, but I'm not sure if I'm doing it right. 
This is what I tried:
y+3=x+4   <---- (That's not necessarily true!)
y=x+1 
2.5+x=4+6  <---- (That's not necessarily true!)
2.5+x=10
x=7.5
y+3=7.5+4
y=7.5+1
y=8.5

No, you need to know this theorem:

When two chords intersect inside a circle, 
the product of the segments of one chord 
equals the product of the segments of the 
other chord. 

So in the small circle, set the product of
the segments of one chord equal to the
product of the two segments of the other
chord.

(x)(4) = (y)(3) or 4x = 3y 

and do the same with the product of the
two segments of the chords of the large 
circle,

(2.5 + x)(4 + 6) = (6 + y)(3 + 2) or
     10(2.5 + x) = 5(6 + y) or
        25 + 10x = 30 + 5y 
        10x - 5y = 5
          2x - y = 1

So solve this system of equations:

4x = 3y
2x - y = 1

and get x = 1.5, y = 2

Edwin