19.
A) 84 : 120 --) 7 : 10, I came up with it by knowing x, # of times ordered,
7(x) : 3(x) sum will be 120 and guessed from there.
B) Well I came up with it trying to get the ratio for A, 84 smoothies.
C) 84 ( smoothies) - 36 ( juice drinks)
20.
A) Ok you first have the birds from the first hour which sum up to 24. Then to calculate what of how many birds you saw for the second hour you use the ratio 2 (cardinals) : 3 ( chickadees) : 3 ( pigeons). Now before you use the ratio you need to know how many birds out of the 36 have not been seen in the first hour so just subtract 36 - 24 = 12. Next you figure out what number you can multiply every bird against to get a sum of 12 birds in total. I figured out it's 1.5 as a multiplier. I know physically it's not possible, but I did all the steps correct and apparently they don't care it's not realistic. I hope this helps you on the homework sheet.
Answer:
a
Step-by-step explanation:
Answer:
The correct option is (A).
Step-by-step explanation:
If the reduced row echelon form of the coefficient matrix of a linear system of equations in four different variables has a pivot, i.e. 1, in each column, then the reduced row echelon form of the coefficient matrix is say A is an identity matrix, here I₄, since there are 4 variables.
![\left[\begin{array}{cccc}1&0&0&0\\0&1&0&0\\0&0&1&0\\0&0&0&1\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D1%260%260%260%5C%5C0%261%260%260%5C%5C0%260%261%260%5C%5C0%260%260%261%5Cend%7Barray%7D%5Cright%5D)
Then the corresponding augmented matrix [ A|B] , where the matrix is the representation of the linear system is AX = B, must be:
![\left[\begin{array}{ccccc}1&0&0&0&a\\0&1&0&0&b\\0&0&1&0&c\\0&0&0&1&d\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccccc%7D1%260%260%260%26a%5C%5C0%261%260%260%26b%5C%5C0%260%261%260%26c%5C%5C0%260%260%261%26d%5Cend%7Barray%7D%5Cright%5D)
Now the given linear system is consistent as the right most column of the augmented matrix is a linear combination of the columns of A as the reduced row echelon form of A has a pivot in each column.
Thus, the correct option is (A).
The answer for the question is x= 12.44, x = 0.56