Solve the system by substitution.
−7x−10y= 40
x=−2y

x= -20, y= 10

Step-by-step explanation:

Label the two equations:

-7x -10y= 40 (1)

x= -2y (2)

Substitute (2) into (1):

-7(-2y) -10y= 40

Expand:

14y -10y= 40

Simplify:

4y= 40

Divide both sides by 4:

y= 40 ÷4

y= 10

Substitute y= 10 into (2):

x= -2y

x= -2(10)

x= -20

answer: i don't understand it

step-by-step explanation: sorry

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