From the general equation of the straight line:
$$$Ax + By + C = 0$$$
We can isolate $$y$$ and we obtain:
$$$\displaystyle y=-\frac{A}{B}x-\frac{C}{B}$$$
which is equivalent to:
$$$y=m \cdot x+n$$$
where $$\displaystyle m =-\frac{A}{B}$$ is the slope of the straight line, and $$n =-C/B$$ is $$y$$-coordinate of the point of intersection of the straight line with the axis $$OY$$; in other words, the value of $$y$$ when $$x = 0$$, that is to say $$y (0) = f (0)$$.
Find the explicit equation of the straight line $$r$$ with implicit equation:
$$$2x + 5y - 26 = 0$$$
Therefore, isolating $$y$$:
$$$\displaystyle y=-\frac{2}{5}x+\frac{26}{5}$$$
where we see that the straight line has slope $$\displaystyle -\frac{2}{5}$$ and that it cuts the axis $$OY$$ in $$y = \frac{26}{5}$$, or at point $$(0, \frac{26}{5})$$.