Answer: 
b) 75
c) $24
<u>Step-by-step explanation:</u>
the difference in the y-values (electricity) divided by the difference in the x-values (students) is the rate of change. 
Electricity = rate of change × students ⇒ 
b) Find s when E = 15

c) Find E when s = 120

9x-3 because you combine like terms
Answer:
100
Step-by-step explanation:
For the right side its 12.5
Answer: 3x^2 + 7x -15
I dunno if u want me to factor it tho