We have to set up 2 different equations if we are to solve for 2 unknowns. The first equation is x = y + 4. One number (x) is (=) 4 more than another (y + 4). Since we have determined that x is larger (cuz it's 4 more than y), when we set up their difference, we are going to subtract y from x cuz x is bigger. The second equation then is

. In our first equation we said that x = y + 4, so let's sub that value in for x in the second equation:

. Expand that binomial to get

. Of course the y squared terms cancel each other out leaving us with 8y + 16 = 64. Solving for y we get that y = 6. Subbing 6 in for y in our first equation, x = 6 + 4 tells us that x = 10. Yay!
Answer:
$110
Step-by-step explanation:
First we would need to find out how many cans of dog food are required.
To find that you would divide 60 by 3.
60/3 = 20
You would then have to multiply that number by how much it costs for each pair of 3 cans, that being $5.50.
20 * 5.50 = $110
Five pencils and two matches are worth greater than thirty paper clips? Need reasoning? Hope this helps :)