It would take Jay 21 minutes to clear the driveway of the snow working alone
The equation is given as:
[tex]\frac 1j + \frac{1}{j + 21} = \frac{1}{14}[/tex]
Take the LCM
[tex]\frac{j + 21 + j}{j(j + 21)} = \frac{1}{14}[/tex]
This gives
[tex]\frac{2j + 21}{j(j + 21)} = \frac{1}{14}[/tex]
Cross multiply
[tex]14(2j + 21) =j(j + 21)[/tex]
Expand
[tex]28j + 294 =j^2 + 21j[/tex]
Collect like terms
[tex]j^2 +21j - 28j - 294 =0[/tex]
[tex]j^2 - 7j - 294 =0[/tex]
Using a graphing calculator, we have:
[tex]j = 21\ or\ x =-14[/tex]
The value of j cannot be negative, because of the context.
So, it would take Jay 21 minutes to clear the driveway of the snow working alone
Read more about rational equations at:
https://brainly.com/question/18446103
