230k views
2 votes
Solve the system using an augmented matrix. Show all work.

{−x−3y=−17
2x−6y=−26

A) x = 4, y = -1
B) x = -3, y = 5
C) x = 3, y = -4
D) x = 2, y = -2

User Sumit Deo
by
7.5k points

1 Answer

4 votes

Final answer:

To solve the system using an augmented matrix, perform row operations to eliminate the leading coefficients and arrive at the reduced-row echelon form of the augmented matrix.

Step-by-step explanation:

To solve the system of equations using an augmented matrix, let's write the system of equations in the form of AX = B, where A represents the coefficients, X represents the variables, and B represents the constant terms:

[-1 -3 | -17]

[2 -6 | -26]

Next, we will use row operations to transform the augmented matrix into row-echelon form or reduced-row echelon form. Using these operations, we can eliminate the leading coefficient in the second row:

[1 3 | 17]

[0 -12 | -10]

Continuing with the row operations, we can divide the second row by -12 to get:

[1 3 | 17]

[0 1 | 5/6]

Finally, by performing the appropriate row operation, we can eliminate the leading coefficient in the first row:

[1 0 | 4]

[0 1 | 5/6]

Therefore, the solution to the system of equations is x = 4 and y = 5/6. Hence, the correct answer is option B) x = -3, y = 5.

User Aaran McGuire
by
7.8k points