Answer:
I wil have traveled 20 miles by the moment I meet my friend
Step-by-step explanation:
Hi
We are going to use de following formula [tex]x_{f}=vt+x_{0}[/tex]
In my case speed will be positive, so [tex]v=15mi/h[/tex] and [tex]x_{0}=0mi[/tex], For my friend speed will be negative, so [tex]v=-12mi/h[/tex] and [tex]x_{0}=36mi[/tex]. Then we can build two equations
(1) [tex]x_{f}=15t+0 \ or \ t=\frac{x_{f}}{15}[/tex]
(2) [tex]x_{f}=-12t+36[/tex]
By replacing (1) in (2) [tex]x_{f}=-12(\frac{x_{f}}{15} )+36=-\frac{4}{5} x_{f}+36[/tex]
Multiplying both sides by 5
[tex]5x_{f}=-4x_{f}+180\\9x_{f}=180\\x_{f}=\frac{180}{9} =20[/tex]
So I wil have traveled 20 miles by the moment I meet my friend.
