Answer:
102
Step-by-step explanation:
I'm going to use m for minutes
Cell carrier 1
0.15 per minute (0.15m)
$26.50 first, and then add on for every minute
cost carrier 1 = 0.15m + 26.50
carrier 2
0.25 per minute (0.25m)
$14.50 first, and then add on for every minute.
cost carrier 2 = 0.25m + 14.50
to find out when they cost the same, make the two costs equal to each other:
0.15m + 26.50 = 0.25m + 14.50
all that's left is to solve for m
0.15m + 26.50 = 0.25m + 14.50
subtract both sides by 0.15 m
26.50 = 0.2m + 14.50
subtract both sides by 14.50
12 = 0.1 m
divide both sides by 0.1
m = 120
the phone carriers will have the same cost at 120 minutes
The correct answer is 4/3
Solving a polynomial inequation
Solving the following inequation:
(x - 8) (x + 1) > 0
We are going to find the sign both parts of the multiplication,
(x - 8) and (x + 1), have when
x < - 8
-8 < x < 1
1 < x
Then we know (x - 8) (x + 1) > 0 whenever (x - 8) (x + 1) is positive
We can see in the figure (x - 8) (x + 1) is positive when x < -8 and x > 1
Then
Answer:B
