The expression should be (2/h)x(k+8).
See the diagram below.

is the height, and

is the slant height.
The height is the distance from the
base of the pyramid to the vertex (the top of the pyramid). It runs perpendicular to the base.
The slant height is the distance from the
base of the triangles which make up its sides to the vertex. It runs perpendicular to this base as well.
Answer:
/75
Step-by-step explanation:
As I couldn't take the radical symbol I used this - "/".
5 /3
If 5 has to come in the radical sign it has to be squared
So, /25 × /3
/25×3
/75
I hope this helps you
4,8 (x+4)=2,16
48 (x+4)=21,6
x+4=21,6/48
x+4= 0,45
x=0,45-4
x= -3,55
first make two triangles using M , so there iwll be 90-45-45, and 30-60-90 then use the side rules of those special triangles