Answer:
Tuna sandwiches cost $1.83 and cheese sandwiches cost $9.9.
Step-by-step explanation:
x + y = 10
2x + 1.5y = 18.5
Multiply the first equation by -2 to eliminate x
-2x - 3y = -20
2x + 1.5y = 5.15
x cancels out and then add
-1.5y = -14.85
y = 9.9; therefore, cheese sandwiches cost $9.9.
Find x with the original second equation
2x + 1.5y = 18.5
2x + 1.5(9.9) = 18.5
2x + 14.85 = 18.5
2x = 18.5 - 14.85
2x = 3.65
x = 1.83; therefore, tuna sandwiches cost $1.83.
hope it helps :)