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Math Help - Find the Area of this shape:

  1. #1
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    Find the Area of this shape:

    The question posed is..

    Find the Area of this shape: (Forgive my crappy art job)





    Can someone help me work this problem out? I thought it was basically LxW but according to my book my answer is wrong. How exactly do you work this problem? Why? (any notes/info is helpful thank you.)
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  2. #2
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    This diagram might help. You are right that it is basically LXW.

    Find the Area of this shape:-mathqin6.jpg

    If you post the answer you and the book got, someone here can tell you if you are right.
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  3. #3
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    Quote Originally Posted by badgerigar View Post
    This diagram might help. You are right that it is basically LXW.

    Click image for larger version. 

Name:	mathqin6.jpg 
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    If you post the answer you and the book got, someone here can tell you if you are right.
    Okay, I did 5mi x 7mi + 4mi x 2mi = 43mi area.

    even Navigating through the books 'answer guide' is hard.. but unless i'm mistaken the book says the answer is 29mi^2
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  4. #4
    is up to his old tricks again! Jhevon's Avatar
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    Quote Originally Posted by E=MChuh? View Post
    Okay, I did 5mi x 7mi + 4mi x 2mi = 43mi area.

    even Navigating through the books 'answer guide' is hard.. but unless i'm mistaken the book says the answer is 29mi^2
    cut it into two rectangles and find the area of each

    draw a horizontal line to complete the top of the larger rectangle. now we have a 4 by 2 rectangle and a 7 by 3 rectangle

    so the area is (4*2) + (7*3) = 8 + 21 = 29 square units


    EDIT: sorry badgerigar, didn't see your post
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  5. #5
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    Imagine it was a complete rectangle, i.e., without the upper right corner cut out. It would measure 5 x 7 and thus have an area of 35 square miles.

    Now, we have to SUBTRACT the area of the upper right, the part that is removed. That is a rectangle with dimensions 2 x 3 (the 2 is given; the 3 is 7-4, as pointed out elsewhere). The rectangle that is removed, thus, has an area of 6 square miles.

    Take the total area of the "complete" rectangle and subtract the removed part:

    35 - 6 = 29 square miles.
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  6. #6
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    Thanks

    ahhh I see how it works now, thanks everyone .
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  7. #7
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    EDIT: sorry badgerigar, didn't see your post
    No need to apologise; you didn't actually duplicate anything I said.
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