Question 480463
Let "c" and "d" be cost per unit bag of chips and container of dip respectively

Given in the problem.... 6 bags of chips and 4 containers of dip cost $34
which is expressed as 
6c+4d=34............(1)

Also given that 4 bags of chips and 2 containers of dip cost $20
which is expressed as 
4c+2d=20........(2)

Multiplying  eqn no. 2 by 2 results in
8c+4d=40..........(3)

Subtracting eqn no 1 from 3 results in
(8c+4d)-(6c+4d)=40-34
8c+4d-6c-4d=6 
2c=6 ( as 4d gets cancelled out)
dividing both sides by 2 
c=3

Now substituting value of c in eqn no.1 to get value of d.....
6*3+4d=34
18+4d=34
Subtracting 18 from either side in above equation results in
4d=16
Dividing both sides by 4
d=4

Ans : cost of one bag of chips $3 and one container of dip $4