Answer
$\frac{x^{2}}{9}-\frac{y^{2}}{36}=1$
Work Step by Step
Here, $a=3$ and also the asymptotes are $y=\pm2x$
which gives $\frac{b}{a}=2$
Put $a=3$ to get $b=6$
The equation of the hyperbola is:
$\frac{x^{2}}{9}-\frac{y^{2}}{36}=1$