X= 10 I did it on my calculator so don’t worry :)
Answer:
9r
Step-by-step explanation:
4r+9r-11r+7r
Combine like terms
13r -11r+7r
2r+7r
9r
1.55 i did that math too it was kinda hard but i did it
#1 There is no area of a cube. There is only a volume.
#2 The formula is

where s is the side.
Substitute 729 in V since that is the volume.

Take the cube root and you will get
9.
So the formula is
and the side is 9.