Step 1:
$36x^2-25y^2=900$
The above equation is divided by $900$ we get,
$\large\frac{x^2}{25}-\frac{y^2}{36}$$=1$
$a^2=25,b^2=36$
$a=5,b=6$
Step 2:
$\large\frac{x}{a}$$\pm\large\frac{y}{b}$$=0$.
Substitute the value of a & b we get,
The equations of the asymptotes are $\large\frac{x}{5}$$\pm\large\frac{y}{6}$$=0$
(i.e) $6x\pm 5y=0$
This is the required equation of the asymptotes to the hyperbola.