C(x) = 10x+500
A. C(O)=A 10.0+500. = 500.e
B. C(25) = 10.25+500 =750
C.c(x)=1500=10x+500
-1 + 6x = - 2 |add 1 to both sides
6x = -1 |divide both sides by 6
x = - 1/6
We manipulate the given equation in order to solve for EC. We do this by cross multiplying.
The resulting equation will be:
EC = (4 x 3)/5
EC = 12/5 = 2.4
Additionally, the side-splitter theorem works for this problem since DE and AC are parallel to each other, therefore splitting the remaining two sides into proportional segments.
Answer:

Step-by-step explanation:
Let m denotes the number of minutes of phone use in a month.
In plan a there is no monthly fee, but the customer pays 8 cents per minute of use.
Total cost of plan a = 
In Plan B the customer pays a monthly fee of $2.40 and then an additional 7 cents per minute of use.
Total cost of plan b = 
To find amount of monthly phone use for which plan a cost more than plan b, solve the inequality
.
