## Hayleymeyer one year ago http://media.education2020.com/evresources/878-12-03-00-00-sur_files/i0070000.jpg

1. Hayleymeyer

|dw:1433950053698:dw|

2. Hayleymeyer

each square is 5. find the surface area, ive been doing this for 3 hours, on this type of stuff.

3. Hayleymeyer

@danicap

4. geerky42

OK you gotta have to count squares. But you got to do it in smart way. OK clearly this is 3D. But imagine looking it at certain angle (front, top, and side), so it would looks like 2D Then there will be SAME number of square on opposite sides of whatever you are "looking" at. Get the plan?

5. Hayleymeyer

got it!

6. geerky42

For example, if you are looking at top, you will kind of see this: |dw:1433950339164:dw|

7. geerky42

then multiply that by 2, for other side (bottom)

8. Hayleymeyer

which would be 16?

9. geerky42

Yes there are 16 squares for TOP and BOTTOM. Now count front.

10. Hayleymeyer

16 for the front

11. geerky42

you would see this:|dw:1433950434314:dw|

12. geerky42

yeah 16. so double that for other sides and you have 32

13. geerky42

Ok now side.

14. Hayleymeyer

14?

15. geerky42

I got 12

16. Hayleymeyer

my bad! counted 2 extra block

17. geerky42

|dw:1433950631697:dw|

18. geerky42

OK now double that. 24

19. geerky42

Now add them all together: 24 + 32 + 16 = ?

20. Hayleymeyer

72

21. geerky42

Yep. So there are 72 squares. Now for each square, what is area?

22. geerky42

5 mm * 5 mm = ?

23. Hayleymeyer

10mm^2

24. geerky42

No. multiply 5 by 5. What do you get?

25. geerky42

A = lw

26. Hayleymeyer

5/5=1

27. Hayleymeyer

im a very slow learner, sorry :(

28. geerky42

To get area, you just multiply length by width, right?

29. Hayleymeyer

yes

30. geerky42

OK, so length of square is 5 and width is also 5

31. geerky42

So you have $$Area = 5\times5$$

32. Hayleymeyer

okay, which would be 25

33. geerky42

Yeah Area of EACH square is 25. And there are 72 squares. So multiply 72 by 25. That would be your surface area.

34. Hayleymeyer

which would be 1,875

35. geerky42

I got 1800?

36. geerky42

$$72\times25$$

37. Hayleymeyer

my bad, I don't no why my calculator is messing up

38. geerky42

OK, so you got 1800, right? So your surfacce area is$SA = \boxed{1800~\text{mm}^2}$

39. geerky42

IS that clear?

40. geerky42

Just got to count the smart way, kinda.

41. Hayleymeyer

thanks so much, I appreciate and thanks for your patience!

42. geerky42

No problem