The companies being considered are:
The company that is concerned with corded telephones
The company that is concerned with cellphones
Let x represent the number of years since 2002 and y represent the total number of accounts
From the information given,
Considering the first company,
Initial number of accounts = 946 x 10^6
The number of accounts fell by approximately 28 million per year. This means that in x years, the number of accounts that would have been lost is
28 x 10^6 * x
= - 28x x 10^6
It is negative because it is reducing
The slope intercept form of a linear equation is expressed as
y = mx + c
where
m = rate of change
c = y intercept of value of y when x = 0
By comparing with the given scenario,