h = 6 cm
The formula for the volume of a rectangular prism is [tex]V = lwh[/tex]. In order to figure out the height you need to divide [tex]wh[/tex] from both sides of the equation. As a result, you'd get [tex]\frac{V}{lw}=h[/tex]. Then you'd rearrange the equation so that it's [tex]h=\frac{V}{lw}[/tex].
[tex]h=\frac{V}{lw}=\frac{120}{4(5)}=\frac{120}{20}=6cm[/tex]
