I need an equation for this algebra problem
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Answer:
2.5 hours
Step-by-step explanation:
Given
The information in the attachment
To solve this question, first we calculate the slope
[tex](t_1,B_1) = (1,19,5\%)[/tex]
[tex](t_2,B_2) = (2,13\%)[/tex]
The slope is:
[tex]m = \frac{B_2 - B_1}{t_2 - t_1}[/tex]
[tex]m = \frac{13\% - 19.5\%}{2-1}[/tex]
[tex]m = \frac{-0.065}{1}[/tex]
[tex]m = -0.065}[/tex]
The equation is calculated as:
[tex]B - b_3 = m(t - t_3)[/tex]
Where
[tex]m = -0.065}[/tex]
[tex](t_3,B_3) = (3,6.5\%)[/tex]
This gives
[tex]B - 6.5\% = -0.065(t - 3)[/tex]
[tex]B - 6.5\% = -0.065t +0.195[/tex]
[tex]B -0.065 = -0.065t +0.195[/tex]
[tex]B = -0.065t +0.195 +0.065[/tex]
[tex]B = -0.065t +0.26[/tex]
To calculate the time at 9.75%.
We take B = 9.75%
So, we have:
[tex]9.75\% = -0.065t +0.26[/tex]
Solve for t
[tex]0.0975= -0.065t +0.26[/tex]
Collect Like Terms
[tex]0.065t= -0.0975 +0.26[/tex]
[tex]0.065t= 01625[/tex]
[tex]t = 0.1625/0.065[/tex]
[tex]t = 2.5[/tex]
Hence, it will take 2.5 hours.