Solve the system by elimination

4x+3y=-5

-x+3y=-10

Subtract the 2nd row from the 1st row

5x = 5

Solve for x in the equation above

x = 1

Substitute x = 1 into any of the two equations above

Let's  pick the first equation; 4x + 3y = -5

4 * 1 + 3y = -5

Solve for y in the equation above

y = -3

Therefore,

x = 1

y = -3

9 sandwiches per hour

step-by-step explanation:

when we have a rate, we want a 1 in the denominator

27/3 = 9

27 sandwiches/ 3 hours = 9 sandwiches/hour