Given model is
[tex]A=8000+8000(0.045t)[/tex]
Substitute A=12981 to find the value of t, we get
[tex]12981=8000+8000(0.045t)[/tex]
Subtracting 8000 from both sides, we get
[tex]12981-8000=8000+8000(0.045t)-8000[/tex]
[tex]4981=8000(0.045t)[/tex]
Multiplying 8000 and 0.045, we get
[tex]4981=360t[/tex]
Dividing both sides by 360, we get
[tex]\frac{4981}{360}=\frac{360t}{360}[/tex]
[tex]t=13.8361[/tex]
Round off nearest tenth, we get
[tex]t=13.8\text{ years}[/tex]
Hence it would take 13. 8 years for the loan amount to $ 12981.
