Answer:
Step-by-step explanation:
If you let y=2x, you can plug it into the other equation.
x+2x=-9
Then solve that equation.
3x=-9
x=-3
Then use y=2x to find y.
y=2(-3)=-6
y=-6
Answer:
A= 4
Step-by-step explanation:
Answer:
406.35
Step-by-step explanation:
40 times $9.45=378
2 times (9.45times1.5)= 28.35
28.35+378= 406.35