## eAnthonyR 3 years ago The diagonals of a square each measure 7 feet. Find the are of the square

1. eAnthonyR

@Loujoelou

2. ajprincess

|dw:1345312296169:dw| Use pythagoras theorem $$a^2+a^2=7^2$$ $$2a^2=49$$ Area=$$a^2$$ find $$a^2$$ from $$2a^2=49$$

3. eAnthonyR

So 2a=49 and then divide both sides eright?

4. eAnthonyR

or just leave thats cool too lol

5. ajprincess

ya divide by 2 to find a^2

6. anonymous

divide the diagonal by $$\sqrt{2}$$ to get the length of the side, then square the result

7. eAnthonyR

ok gotchu Next question. Two sqaure are similar. The ratio of a set of sides is 2:4. whatis the ratio of their area?

8. anonymous

if you call the diagonal $$d$$ then the length of the side is $$\frac{d}{\sqrt{2}}$$ and area is $$\frac{d^2}{2}$$

9. eAnthonyR

ok gotchu Next question. Two sqaure are similar. The ratio of a set of sides is 2:4. whatis the ratio of their area?

10. Loujoelou

|dw:1345313796722:dw| This is what the information gives us so far. It splits our square into 2 triangles and we can do pythageoren theorem what the sides are. A^2+B^2=7^2. is the formula for the pythageroen theorem. A^2+B^2=49. We simplified this here. They are both the same thing however because the sides of a square are equal so we really have 2A^2=49. We divide both sides by 2, and get A^2=24.5 Now we have to do the opposite of squaring, and that's square root. Now we have A^2= $\sqrt{24.5}$ This is one side of the square, and we would do $\sqrt{24.5}*\sqrt{24.5}$ to get our area of this square

11. eAnthonyR

Lol i got the answer xD thanks man :) Next question Two sqaure are similar. The ratio of a set of sides is 2:4. whatis the ratio of their area?

12. Loujoelou

|dw:1345314609037:dw| with the info. above, that's what we get and for the first square, let's find the area. Area= 2*2; Area=4. So that means for our 1st square we have an area of 4. Now we do the same for the 2nd square, we do Area= 4*4; Area=16. That means the area of both squares is 4 & 16. We put this into a ratio, and we have 4:16, which can be simplified to 1:4 if needed.

13. eAnthonyR

lol wow haha i wanted to make another question so i could give you another medal haha

14. Loujoelou

Lol medals don't really matter that much to me. :) I enjoy helping others a lot more :D

15. eAnthonyR

hah ok so we will stay here <3

16. eAnthonyR

@Loujoelou

17. Loujoelou

sure no prob. :)

18. eAnthonyR

There you goo @Loujoelou

19. eAnthonyR

20. Loujoelou

I'm still here. :) Give me a bit of time to solve :D

21. eAnthonyR

ok :)

22. Loujoelou

K. so yeah that's the square and you labelled it corretly :). We would do the same thing as we would with regular numbers, and we will multiply (2x+10)(4), and that would give us 8x+40=80. Do you know how to do the rest? :)

23. eAnthonyR

8x+40=80 -40 -40 8x=40 x=5<3

24. eAnthonyR

am i right?

25. Loujoelou

Yep good job!! :)

26. Loujoelou

and if you wanted to double check this problem, you would put x back into the probolv e. 5 and solve. (2(5)+10)=20, and 20*4=80 so this would be correct :)

27. Loujoelou

problem as*

28. eAnthonyR

iight hold on i have to right the next one again <3

29. Loujoelou

K and hey you got nice handwriting.

30. eAnthonyR

haha ik all the girls love it <3

31. eAnthonyR

32. Loujoelou

K :) All you would do here, is find the area of the bigger rectangle first. 200*140=28000. Now we find the area of the pool. 30*15=450. Finally all we do is subtract them, 28000-450=answer ft.^2

33. eAnthonyR

Thank you soo Much <3

34. eAnthonyR

Let me plug in the answers into my hw brb give me a minute

35. Loujoelou

No prob. :) and okay :)

36. eAnthonyR

37. Loujoelou

Yeah :)

38. eAnthonyR

Thank you :) hold on i have to look for another Hw page

39. Loujoelou

do you do virtual school o.O?

40. eAnthonyR

yes hahah

41. eAnthonyR

Find the area of a rhombus with diagonals of 4ft and 5ft . :) But im done wit virtual school im doing hw now

42. eAnthonyR

@Loujoelou

43. Loujoelou

Oh okay I do some virtual school as well :)

44. eAnthonyR

cools xD

45. eAnthonyR

Find the area of a rhombus with diagonals of 4ft and 5ft . :)

46. eAnthonyR

if ur there xD

47. Loujoelou

K so all we do is D1*D2/2=Area. D1=Diagonal 1 & D2= Diagonal 2

48. Loujoelou

49. eAnthonyR

so 4*5 =20/2=10 xD right?

50. Loujoelou

Yep :)

51. eAnthonyR

Hahah Yeahhh xD Find the base of the parallelogram that has an area of 228meters squared and has a hheight of 12meters

52. eAnthonyR

BRB GIVE ME A COUPLE OF mINUTES OK <3

53. Loujoelou

K :)

54. Loujoelou

@eAnthonyR

55. eAnthonyR

YAYYYY xD ahah :p

56. eAnthonyR

Find the base of the parallelogram that has an area of 228meters squared and has a hheight of 12meters If you dont mind xD

57. Loujoelou

K so the formula of a parallelogram is Area=Base*Height. From the info above, we got 228=b*12. Can you find the base now? :)

58. eAnthonyR

Divide right :)?

59. Loujoelou

Yep. divide 12 on both sides and get b=228/12

60. eAnthonyR

Find the missing diagonal of the rhombus that has an area of 12 feet sqaures and one diagonal of 6ft. If you may can you explain this one to me so i can understand alittle bit

61. Loujoelou

K. To find the area of a rhombus we do D1+D2/2=Area. The D1/2 are the diagonals. Using the info. we have we get 6+D2/2=12

62. eAnthonyR

So do we subtract 12-6? and then thats the D2?

63. Loujoelou

No, here we multiply the 2 on both sides, so we get 6+D2=24. Then we subtract both sides by 6 and get D2=18 :)

64. Loujoelou

No, here we multiply the 2 on both sides, so we get 6+D2=24. Then we subtract both sides by 6 and get D2=18 :)

65. eAnthonyR

Ohhhh we multiply? Ok ok

66. eAnthonyR

wait but 18 isnt an answer ..

67. Loujoelou

Wait whoops yeah I made a mistake sry let me see.

68. eAnthonyR

lol ok <3 its ok xD

69. Loujoelou

No wait if we double-check what we got, in the formula D1+D2/2=12 and put 6 & 18 in, 18+6/2=12;24/2=12;12=12 it's right.

70. eAnthonyR

thats weird cause 18 isnt an answer hold on maybe i made a mistake

71. Loujoelou

What are the choices?

72. eAnthonyR

4 6 8 2

73. eAnthonyR

Nope i didnt make a mistake

74. Loujoelou

I can't seem to find what I did wrong sry. :/ Try posting it as a question, other help you on that one.

75. eAnthonyR

i posted it xD

76. eAnthonyR

join it

77. Loujoelou

Then once we find out what that one is I can help you w/ another one okay?

78. eAnthonyR

okkk :)