Step-by-step explanation:
Given that,
- Length of the one portion of the board = x feet
- Length of the another portion = (7x – 9) feet
According to the question,
Total length = Sum of the length of the two pieces
Total length = {x + (7x – 9)} feet
Total length = {x + 7x – 9} feet
<u>Total length = (8x – 9) feet</u>
Therefore, the total length of the board as a simplified expression in x is (8x – 9) feet.
For this case we have the following system of equations:
5x + 3y = 17
-8x - 3y = 9
We can rewrite the system like:
Ax = b
Where,
A = [5 3; -8 -3]
b = [17; 9]
x = [x; y]
The determinant of matrix A is given by:
lAl = ((5) * (- 3)) - ((3) * (- 8))
lAl = (-15) - (-24)
lAl = -15 + 24
lAl = 9
Answer:
The determinant for solving this linear system is:
lAl = 9
Given:
The expression is

To find:
The value of the given expression closest to the whole number.
Solution:
We have,

Cancel out the common factors from each fraction.




Therefore, the value of the given expression is 1.
2x -20 -1 =0
2x -21=0
2x=21
x= 10.5
The best approximation for the solution to this system of equations is (-2.2,-3)
Option C is correct.
Step-by-step explanation:
Solving the system of equations to get the exact value of x:

Let

Putting value of y from eq(1) into eq(2)



So, Value of x is -2.2
The best approximation for the solution to this system of equations is:
x=-2.2 and y = -3
(-2.2,-3)
Option C is correct.
Keywords: System of equations
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