Assuming that the cost per minute is the same for both months and the plan fee is the same, you can use y=mx+b for this
y is the cost of the phone plan, x is the cost per minute and b is the start cost.
so 19.41=25x+b for the first month
and 45.65=380x+b for the second month
solve both for b you get:
19.41-25x=b and 45.65-380x=b. from this we get
19.41-25x=45.65-380x
solve for x
328x=26.24 and x=0.08
this means the cost per minute is 0.08c/min (answer A)
rewrite the equation to calculate b, and where this time, the x is the number of minutes talked.
y=0.08x+b and plug in one of the two months
45.65=0.08 * 380 + b
Solve for b and b is 15.25
so the final equation is
y=0.08x+15.25 (answer B)
Answer: x<-16
Step-by-step explanation:
Answer:
It is a decreasing function for 0 < b < 1.
Step-by-step explanation:
Logarithm function:
The logarithm function is given by:
The base b determines if the function increases or decreases.
For 0 < b < 1, the function decreases.
For b > 1, the function increases.
In this question:
By the definition above, it is a decreasing function for 0 < b < 1.
Answer:
6 2/6 in fractions or 6.3333.
