## anonymous 3 years ago I need some help with Geometry, Finding Total Area in Prisms.

1. anonymous

Si, si

2. anonymous

What is the question?

3. anonymous

Find the Total Area of the Prism:

4. anonymous

5. anonymous

@johnsonshelby

6. anonymous

Find the area of each side and add together... that's surface area I'm having a brain fart haha What is it you want to find?

7. anonymous

Thats gross.

8. anonymous

I want to find total Area

9. anonymous

T.A. = ph + 2B

10. anonymous

Rho as in density, right?

11. anonymous

Rho?

12. anonymous

Greek letter p

13. anonymous

perimeter of the base times height of the prism + 2Base = Total Area

14. anonymous

Well the 2B part is easy. 2(area of the triangles)

15. anonymous

Area of Triangle : 1/2 times 9 "correct" ?

16. anonymous

1/2 time base of the triangle times the height of the triangle. Because you are only given the base, you need to find the height.

17. anonymous

And to find the height we use pythag theorem correct?

18. anonymous

So your new base would be 1.5 and the hypo would still be 3, yep

19. anonymous

So the height would be a^2?

20. anonymous

c= 3, b=1.5, and yep a= a

21. anonymous

so when you plug into pythag, you would get that

22. anonymous

So A= √6.75 ?

23. anonymous

Yeah!

24. anonymous

I have to get to my orgo class in 10 minutes, can you take it from here?

25. anonymous

So i find the area of the triangle and multiply it by 2 Then i add ?

26. anonymous

add that to the (perimeter of the base x height), which would be (3+3+3)(6)

27. anonymous

Area of Triangle = 1.5√6.75 correct?

28. phi

btw, people would write $\sqrt{6.75}$ as $\frac{3 \sqrt{3}}{2}$

29. anonymous

Okay i got it. Thanks so much!! I just needed a refresh it's been awhile :)

30. anonymous

So it would be 4.5√3 / 2 @phi ?

31. phi

generally you don't mix decimals and fractions i.e. 4.5/2 If you have a multiple choice you probably would see the answer as a pure fraction $\frac{4}{9}\sqrt{3}$

32. phi

double that for the other triangle now you have 3 faces that all look the same size 3x6 3 faces each 18 = 54 plus the two triangles 8/9 sqrt(3)

33. anonymous

Other triangle?

34. phi

you have two triangles (the ends) and 3 "side faces" right?

35. anonymous