ANSWER
24
EXPLANATION
For a matrix A of order n×n, the cofactor 
of element 
is defined to be
is the minor of element equal to the determinant of the matrix we get by taking matrix A and deleting row i and column j.
Here, we have
M₁₁ is the determinant of the matrix that is matrix A with row 1 and column 1 removed. The bold entries are the row and the column we delete.
Since the determinant of a 2×2 matrix is
it follows that
so 
The answer is: " 128 oz. " .
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There are: " 128 oz. " (in " 8 lbs." ) .
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Explanation:
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Set up a proportion; as a fraction; as follows:
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400/ 25 = x / 8 ;
in which: "x" = the number of "ounces [oz.] there are in "8 lbs." ;
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We shall solve for "x" , the answer to the problem:
Cross-factor multiply:
25x = (400) * 8 ;
→ 25x = 3200 ;
Divide each side of the equation by "25" ; to isolate "x" on one side of the equation; & to solve for "x" ;
→ 25x / 25 = 3200 / 25 ;
→ x = 128 .
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Answer: " 128 oz. " .
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There are: " 128 oz. " (in " 8 lbs." ) .
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Note of interest: " 16 oz. = 1 lb. " (exact conversion).
So; "8 lbs. <span>= ?</span> oz. " ;
→ " 8 lbs. * (16 oz/ 1 lb) = ( 8 * 16) oz. = 128 oz. ; → which is our answer!
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62 divided by 0.25 is 248
Y-Intercept =(−8)
Go to the graph and plot the point the point (0,−8) on the y-axis.
Then rise 4 and run 1. Plot the point (1,−4)
Then again "rise 4" and then "run" 1. Plot the point (2,0)
