Hello!
To find the volume of the prism you first have to find the volume of a cube
To do this you use the equation

V is volume
a is side length
Put in the values you know

Solve
V = 0.125
Now to find the volume of the prism you multiply the volume of one cube by the amount of cubes in the prism
0.125 * 8 = 1
The answer is 1 cubic inch
Hope this helps!
X = 42 (i’m not sure your giving enough information)
1) Equation: x^2 = 7x
2) Transpose terms: x^2 - 7x = 0
3) Factor: x (x - 7) = 0
4) Solutions: x = 0 and x - 7 = 0 => x =0 and x = 7.
Answer: 0 and 7