Lets say that variable x=total number of hotdogs, and variable y=total number of drinks. Our first equation will calculate the total cost.
2x+1y=11. We are multiplying the price by the total number of each item then adding them together, since they spent a total of $11. Our second equation will calculate the number of items.
x+y=8.
To solve, we will isolate x in the second equation. x=8-y We will substitute that for x in the first equation. 2(8-y)+1y=11 Distributive property. 16-2y+1y=11 Combine like terms. 16-y=11 Isolate y to solve. y=5 Then we plug y into the second equation and solve for x. x+5=8 Subtract 5 from both sides. x=3
