Remember that
the volume of the figure is equal to the volume of the pyramid plus the volume of the rectangular prism
so
step 1
Find out the volume of the rectangular prism
V=L*W*H
substitute given values
V=(8)(8)(14)
V=896 in3
step 2
Find out the volume of pyramid
V=(1/3)Bh
where
B is the area of the square base
h is the height of the prism
Find out the height of pyramid
Applying Pythagorean Theorem
10^2=h^2+4^2
h^2=100-16
h^2=84
h=√84 in=2√21 in
Find the volume
V=(1/3)(8^2)(2√21)
V=(128/3)√21 in3
step 3
the total volume is
V=896+(128/3)√21 in3