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# Area of a Rectangle watch

1. This maybe the most stupid question ever, but isn't the area of this rectangle 12 i.e. (3x4) height by width???

the co-ordiantes are (-1,0) (0,-3) (4,0) (3,3)

2. Area= height x width is true, but neither 3 nor 4 are heights or widths. Thinking of it as two triangles is an easier way to find the area. (Doesn't involve the square roots you'd get using pythagoras). Where did you get 3 and 4 from?
3. (Original post by Hathlan)
Area= height x width is true, but neither 3 nor 4 are heights or widths. Thinking of it as two triangles is an easier way to find the area. (Doesn't involve the square roots you'd get using pythagoras). Where did you get 3 and 4 from?

Looking at y co-or: 4 across

Looking at x co-or: 3 up
4. You need to split it into three triangles, find the area of the triangles and then add them together. Or tracing paper and be cool, but I'm guessing they want you to work out the area of the triangles.
5. (Original post by emmaxoxo)
This maybe the most stupid question ever, but isn't the area of this rectangle 12 i.e. (3x4) height by width???

the co-ordiantes are (-1,0) (0,-3) (4,0) (3,3)

Find the distance between -1 and -3 and then between -3 and +4.The area=LxB
6. (Original post by emmaxoxo)

Looking at y co-or: 4 across

Looking at x co-or: 3 up
But it's not 3 up, is it? It's 3 up and one across. Consider a line that was 3 up and 20 across. Is it the same length as a line that's just 3 up?
7. (Original post by emmaxoxo)

Looking at y co-or: 4 across

Looking at x co-or: 3 up
You assume the length = 4 and width = 3 by looking at the diagram. However you can find the length of rectangle by using (4,0) and (0,-3). You would get root 25 which is 5. It is therefore far easier consider the triangle below the x line where you get h = 3 and b = 5.
8. its pretty simple just divide it into triangles

the bottom right triangle, you know 3 and 4 so work out the hyp... it's 5, classic one 3 4 5.

the bottom left triangle, you know 1 and 3, root 10.....

hmmm maybe not
9. I can't see an easier way to do this than splitting it into 4 integrals etc... to do that first integral I'd recommend using an substitution. Perhaps you could exploit the spherical symmetry of but I'm not exactly sure how that would work out here...
10. The easiest solution is in the opening post. Why does everyone try make simple things seem more complex than it is?
11. (Original post by Totally Tom)
I can't see an easier was to do this than splitting it into 4 integrals etc... to do that first integral I'd recommend using a substitution.
lol.
12. I think she's missed a crucial point in that full stops are supposed to remain inside the parenthesis when the whole sentence is inside one.
13. (Original post by emmaxoxo)
This maybe the most stupid question ever, but isn't the area of this rectangle 12 i.e. (3x4) height by width???

the co-ordiantes are (-1,0) (0,-3) (4,0) (3,3)

The blue line is 5 units long.
The height of triangle is 3 units.

Area of triangle is 5 x 3 / 2

The area of whole rectangle is therefore 15

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