Using linear functions, we have that:
A.
For Company A: [tex]S_A(n) = 31000 + 3000n[/tex]
For Company B: [tex]S_B(n) = 38000 + 2000n[/tex]
B. The salaries will be the same after 7 years.
A linear function is given by:
[tex]y = mx + b[/tex]
In which:
Item a:
[tex]S_A(n) = 31000 + 3000n[/tex]
[tex]S_B(n) = 38000 + 2000n[/tex]
Item b:
[tex]S_A(n) = S_B(n)[/tex]
Then
[tex]31000 + 3000n = 38000 + 2000n[/tex]
[tex]1000n = 7000[/tex]
[tex]n = \frac{7000}{1000}[/tex]
[tex]n = 7[/tex]
The salaries will be the same after 7 years.
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