## anonymous 5 years ago What is the volume of this composite solid? A)588in3 B)784in3 C)915in3 D)980in3

1. anonymous

2. anonymous

looks like this is made up of 3 objects: 2 cubes and a triangular prism

3. anonymous

yes

4. anonymous

you have all the dimensions, so you just need to find the volume of each object and sum them

5. anonymous

yes

6. anonymous

but how?

7. anonymous

volume is $length * width * height$

8. anonymous

for instance, with the first rectangular prism on the left, 8in by 7in by 7in

9. anonymous

cool

10. anonymous

triangular prism?

11. anonymous

volume is the product of those 3 values, and the same for the other rectangular prism, now with the triangular prism just remember that $A=\frac{1}{2}*base*height$

12. anonymous

so you then multiply A by the 3rd dimension

13. anonymous

so, length∗width∗height A=1\2∗base∗height

14. anonymous

and because you are multiplying values with "inches" as the units, the volume is in inches cubed, $in^3$

15. anonymous

thank you

16. anonymous

no problem, if you need to check your answer I'm around

17. anonymous

hey moderator my computer say its forbidden to get on here why is that

18. anonymous

what do i use for the triangular prism?

19. anonymous

dpfan

20. anonymous

yes?

21. anonymous

looking at the picture, it looks as though the length of the left side the triangle is equal to 8 and the length of the other side is equal to 7....

22. anonymous

7*7*8 = 392 7*7*8 = 392 8*7/2=28 so 392+392+28=812in3

23. anonymous

but 812 is not in the decisions