What I did was to cut the figures into 2 separate figures, So that i can have a regular octagonal right prism. Then I computed for the regular's volume. Since the angle is 45 I assumed that the remaining figure is half the regular octagonal prism i separated. Therefore, the total volume= regular x 1.5

What I did was to cut the figures into 2 separate figures, So that i can have a regular octagonal right prism. Then I computed for the regular's volume. Since the angle is 45 I assumed that the remaining figure is half the regular octagonal prism i separated. Therefore, the total volume= regular x 1.5

may I know what is the title and author of your book? pls.

Eto gamit niya siguro sir

Alternate solutions are encouraged......