
Patrick B. answered 04/17/21
Math and computer tutor/teacher
2 2 -1 14
1 -3 1 -30
-1 1 0 12
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Row3 = Row2 + Row3;
row1 = -2 * row2 + row1;
0 8 -3 74
1 -3 1 -30
0 -2 1 -18
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row1 = 4 * row3 + row1
0 0 1 2
1 -3 1 -30
0 -2 1 -18
per equation #1 : z = 2
per equation #3: -2y +z = -18
-2y + 2 = -18
-2y = -20
y = 10
Per equation #2:
x - 3(10) + 2 = -30
x - 30 + 2 = -30
x - 28 = -30
x=-2
x=-2, y=10, z = 2