Answer:
Average rate of change = -6
Step-by-step explanation:
The average rate of change over the interval (a,b) is given by;
[ f(b) - f(a)] / (b-a)........................where interval is (a,b)
(a,b) interval =(-3,1)
Where;
f(x)= -12 (x+2)² +5

Cost of month plan = $40
Cost of minutes used = $0.45 after 700 minutes
Total cost = $48.10
Let x be the total minutes used
Total cost = 40 + 0.45(x - 700)
------------------------------------------------------------------
Form the equation and solve x
------------------------------------------------------------------
40 + 0.45(x - 700) = 48.10
40 + 0.45x - 315 = 48.10
0.45x - 275 = 48.10
0.45x = 48.10 + 275
0.45x = 323.10
x = 323.10 ÷ 0.45
x = 718
------------------------------------------------------------------
Answer: John had used 718 mins this month
------------------------------------------------------------------
Answer:
$300
Step-by-step explanation:
10% = .1 and each TV costs 120 so .1*120=12 then you take 12*25 since 12 is the money he makes for seeling the tv multiplied by the total TV's sold and you get 300 so Mike makes $300
I believe A and B are the ones. As for explaining? hmm. I would honestly say that any number to the right of a number is a tenth of the place above it. But then again, it's optional to explain ;P