Question 1059714
.
How do I solve this system using an augmented matrix?

–x – 3y = –17
2x – 6y = –26
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Solution set:

<pre>
x1 = 2
x2 = 5
</pre>

<pre>
Your matrix

&#8470;	X1	X2	b
1	-1	-3	-17
2	2	-6	-26

Find the pivot in the 1st column in the 1st row (inversing the sign in the whole row)

&#8470;	X1	X2	b
1	1	3	17
2	2	-6	-26

Multiply the 1st row by 2

&#8470;	X1	X2	b
1	2	6	34
2	2	-6	-26

Subtract the 1st row from the 2nd row and restore it

&#8470;	X1	X2	b
1	1	3	17
2	0	-12	-60

Make the pivot in the 2nd column by dividing the 2nd row by -12

&#8470;	X1	X2	b
1	1	3	17
2	0	1	5

Multiply the 2nd row by 3

&#8470;	X1	X2	b
1	1	3	17
2	0	3	15

Subtract the 2nd row from the 1st row and restore it

&#8470;	X1	X2	b
1	1	0	2
2	0	1	5
</pre>