Answer:
8.7 cm
Step-by-step explanation:
You know the relationship between the diagonal of a rectangular prism and the sides as [tex]d^2 = x^2 + y^2 + z^2[/tex] where x, y and z are the three dimensions of the prism. from your data, [tex]25^2 =18^2 + 15^2 + z^2[/tex] or [tex]z^2 = 25^2 -18^2 - 15^2[/tex]. With some simple calculation you get[tex]z^2 = 625 - 324 - 225 = 76[/tex], or [tex]z= 8.7178....[/tex]
