Answer:
The monthly cost = $9 + $0.39x
Step-by-step explanation:
The answer is -7
2x-3(x+4)=-5
Multiply by -3
2x-3x-12=-5
Collect like terms
-x-12=-5
Move constant to the right to change its sign
-x=-5+12
Add
-x=7
Change the signs
x=-7
<span>potential; kinetic is the answer.</span>