## Precalculus (10th Edition)

$a=2$ $b=3$ $x$-axis
For the hyperbola $\dfrac{x^2}{4}-\dfrac{y^2}{9}=1$, the value of $a$ is $\sqrt{4}=2$; the value of $b$ is $\sqrt 9=3$; and the transverse axis is the $x$-axis.