Question

1)9x-10y=5 2)3y-9x=5.6​

Answer 1

$1)9x - 10y = 5 \\ 9x - 10y - 5 = 0 \\ f(x,y) = 9x - 10y - 5 \\ f_{x} = 9 \\ f_{y} = - 10 \\ \frac{dy}{dx} = - \frac{9}{ - 10 } \\ \frac{dy}{dx} = \frac{9}{10}$

$2)3y - 9x = 5.6 \\ 3y - 9x - 5.6 = 0 \\ f(x,y) = 3y - 9x - 5.6 \\ f_{x} = - 9 \\ f_{y} = 3 \\ \frac{dy}{dx} = - \frac{ - 9}{3} \\ \frac{dy}{dx} = - ( - 3) \\ \frac{dy}{dx} = 3$