## anonymous one year ago 6.) Find the surface area of the regular pyramid shown to the nearest whole number. The figure is not drawn to scale. http://assets.openstudy.com/updates/attachments/55bff878e4b03325500374c7-lollygirl217-1438647128464-as.jpg my answer: 1,125 m^2. is that correct? 7.) What is the surface area of a conical grain storage tank that has a height of 37 meters and a diameter of 16 metes? Round the answer to the nearest square meter. my answer: 1152 square meters.

1. anonymous

is that correct?

2. anonymous

@triciaal

3. anonymous

@Zale101 @Jhannybean

4. anonymous

Hello jhanny can you stay, many of you come and then leave...

5. Jhannybean

The surface area of a hexagonal pyramid is defined by this funky formula $A= \frac{3\sqrt{3}}{2}a^2+3a\sqrt{h^2+\frac{3a^2}{4}}$

6. Jhannybean

We can begin solving this by using the given information to find the height $$h$$ of our hexagonal pyramid |dw:1438661575125:dw|

7. Jhannybean

Using the pythagorean theorem for right triangles,... $h=\sqrt{12^2-(7.5\sqrt{3})^2} =~?$

8. Jhannybean

@Lollygirl217 ?

9. anonymous

Sorry, was I wrong? @Jhannybean

10. anonymous

@Zale101 am i wrong?

11. Jhannybean

Im looking for you to work out the problem with me and you yourself will see whether your answer is right or wrong :P

12. anonymous

I just need to know, yes or no. I dont really have much time.

13. anonymous

i literally only have a day left until I have to turn in a whole load of work so >.<

14. Jhannybean

But now that you have the information to solve for h, we can find our "$$a$$" |dw:1438662349721:dw|

15. Jhannybean

Im sorry, Im helping you solve this to help you understand how to work the problem, I don't have the answer, but I can help you find it :)

16. Jhannybean

Now if we can find $$x$$ using trig, then you can double it to find the base length $$a$$ $\tan(30) = \frac{x}{7.5\sqrt{3}} \rightarrow ~ x=7.5\sqrt{3}\tan(30)$$a=2x$ Therefore if you find x, just double it and you will have the base, $$a$$

17. Jhannybean

And now that you have both $$h$$ and $$a$$, plug it into your funky formula and solve :)

18. anonymous

...

19. anonymous

so you are telling me I got it wrong then?

20. Jhannybean

Nope.

21. anonymous

...no offense but you are wasting my time.

22. Jhannybean

Again, I'm not here to give you answers. That's against the code of conduct on openstudy. @ganeshie8

23. anonymous

its NOT asnwers, its to see if i know it or not