9514 1404 393
Answer:
A. 3×3
B. [0, 1, 5]
C. (rows, columns) = (# equations, # variables) for matrix A; vector x remains unchanged; vector b has a row for each equation.
Step-by-step explanation:
A. The matrix A has a row for each equation and a column for each variable. The entries in each column of a given row are the coefficients of the corresponding variable in the equation the row represents. If the variable is missing, its coefficient is zero.
This system of equations has 3 equations in 3 variables, so matrix A has dimensions ...
A dimensions = (rows, columns) = (# equations, # variables) = (3, 3)
Matrix A is 3×3.
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B. The second row of A represents the second equation:

The coefficients of the variables are 0, 1, 5. These are the entries in row 2 of matrix A.
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C. As stated in part A, the size of matrix A will match the number of equations and variables in the system. If the number of variables remains the same, the number of rows of A (and b) will reflect the number of equations. (The number of columns of A (and rows of x) will reflect the number of variables.)
Answer:
A) Divide 20 by 2 and then add 8 to the result
Step-by-step explanation:

Answer:
2.a)11.355 b)0.94625
3. divide 6 by 4
4. 0.8kg, 800g
Step-by-step explanation:
To convert one measurement to another you need to set it up so that the old measurement gets cancelled out when you multiply the conversion ratio.
2a)
the gallons on top and bottom get cancelled out leaving you with the measurement that you want
2b) 
3) 
4) 

Answer:
Discrete; number of Months after the first year; amount remaining on the card.
Step-by-step explanation:
The value of the card strictly loses $2.50/month after the first year of purchase. This means that the values can only be $22.50, $20, etc. If it were continuous, it would lose an amount that led up to $2.50, meaning that you could have values such as $23.48 and $24.07. We cannot have these values, therefore the relationship is discrete.
As time passes, the amount of money in the card changes. As the amount of money in the card depends on the number of months, we can say that the number of months is the independent variable while the amount of money on the card is the dependent variable.
Hope this helps.