If the cube shown is 7 centimeters on all sides what is the length of the diagonal x.

There's no cube shown but we can guess the diagonal is the long diagonal.  

In a rectangular parallelpiped (aka a box) with dimensions a × b × c the long diagonal x satifies a 3D version of the Pythagorean Theorem,

x² = a² + b² + c²

In a cube a=b=c

x² = 3a²

x = a√3

7√3

step-by-step explanation:

. your answer will contain x - and y -terms. (1 point) x ( ¿¿ 2 − 7 ) 2 +( y 2 − 9 ) 2 √ ¿ 12. what is the distance from the directrix (the crocodile river) to the point ( x , y )? write this equation. your answer will contain a y -term.