How do you calculate the area of a parallelogram using a determinant matrix?

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To calculate the area of a parallelogram using a determinant matrix, the absolute value of the determinant of a 2x2 matrix formed by the vectors is used. The correct matrix is constructed from two adjacent vertices of the parallelogram. In this case, confusion arises from using different pairs of points, leading to inconsistent determinant values. The area should match the geometric calculation of the parallelogram's dimensions, which in this case is 30. Identifying the correct vectors and ensuring proper matrix formation is crucial for accurate area calculation.
niteshadw
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How co you claculate the are a pallelogram determined by points (-2, -2), (0, 3), (4, -1) and (6, 4)...I've seen an example wher a 2x2 determinant matrix was used, but I don't remember how to do it...
 
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The absolute value of the determinant of a 2x2 matrix is the area of the parallelogram determined by the column (or row) vectors of the matrix.
 
I was explained that I should take the opposite points, in a form of
|x1 x2|
|y1 y2| and if the parallelogram is above the x axis, then the area is positive else its negative...so the determinants I have tried,

|-2 6|
|-2 4| and det = 4 but if I use the other two points I get a different answer

|0 4|
|3 -1| and det = 12 but once I draw the parallelogram I found the area to be 6x5=30...what am I doing wrong?
 
You've drawn the parallelogram. So can you see the vectors which determine that parallelogram?
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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