I have this problem:
From this problem, I created my equation, which is:
$\tan \theta$ = $x/y$
Deriving the equation, I got:
$\sec^2 \theta$ * $d \theta / dt$ = $(y*dx/dt-x*dy/dt)/y^2$
After finding the hypotenuse, I inputted everything needed for the derived equation.
$(8.06/4)^2$ * $d \theta / dt$ = $(4*140-7*160)/16$
I then got:
$d \theta / dt$ = -8.62 rad / h
I believe my process is correct, because the derived equation involved fits with the quotient rule, but in the end the assignment says I am wrong. I'm not sure if I answered my own question or if I am missing something within my process.