This is a systems problem. Two variables to find. ( I assume that 2 and 3 means dollars )

S = sodas

D = hot dogs

S + D = 3000

2S + 3D = $7000

We will use substitution with the top equation.

D = 3000 - S

------Now, substitute this into bottom equation

2S + 3(3000 - S) = .7000

2S + 9000 - 3S = 7000

- S = - 2000

**S = 2000**

**------Sodas are 2000 in number sold.**

**So, 1000 hot dogs were sold.**