Answer
One cup of coffee costs 2 dollars
Explanation
Let the cost of 1 sandwich be s dollars
Let the cost of a cup of coffee be c dollars
Carla can buy 4 sandwiches and 3 cups of coffee for 20 dollars
4s + 3c = 20 ............. equation 1
Steve can buy 3 sandwiches and 4 cups of coffee for 18.50 dollars
3s + 4c = 18.50 .......... equation 2
We can then bring the two equations together
4s + 3c = 20
3s + 4c = 18.50
Solving this equation simultaneously, we obtain that
s = 3.50
c = 2
Hope this Helps!!!
