we know that
The volume of the first cube is
(5h^2)^3
while
the volume of the second cube is
(3k)^3
so
their total volume is
(5h^2)^3 + (3k)^3
We can use the special formula for factoring a sum of two cubes:
x^3 + y^3 = (x + y)(x^2 - xy + y^2)
(5h^2)^3 + (3k)^3 = (5h^2 + 3k)((5h^2)^2 - (5h^2)(3k) + (3k)^2)
= (5h^2 + 3k)(25h^4 - 15(h^2)(k) + 9k^2)
the answer is
![(5 h^(2) +3k)(25 h^(4)-15 h^(2)k+9k^(2) )](https://img.qammunity.org/2019/formulas/mathematics/high-school/k7ptrhghq7c6augdvqocqgdssedhbyzhqu.png)