SOLUTION: Solve using augmented matrices. 3x1 + 2x2 = 7 x1 - x2 = -1 Explain to me this problem step-by-step please

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Question 1178499: Solve using augmented matrices.
3x1 + 2x2 = 7
x1 - x2 = -1
Explain to me this problem step-by-step please
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

3x%5B1%5D+%2B+2x%5B2%5D+=+7
x%5B1%5D+-+x%5B2%5D+=+-1


Your matrix

matrix%282%2C3%2C%0D%0A3%2C%092%2C%097%2C%0D%0A1%2C%09-1%2C%09-1%29

Find the pivot in the 1st column and swap the 2nd and the 1st rows

matrix%282%2C3%2C%0D%0A1%2C%09-1%2C%09-1%2C%0D%0A3%2C%092%2C%097%29


Eliminate the 1st column

matrix%282%2C3%2C%0D%0A1%2C%09-1%2C%09-1%2C%0D%0A0%2C%095%2C%0910%29


Make the pivot in the 2nd column by dividing the 2nd row by 5

matrix%282%2C3%2C%0D%0A1%2C%09-1%2C%09-1%2C%0D%0A0%2C%091%2C%092%29


Eliminate the 2nd column

matrix%282%2C3%2C%0D%0A1%2C%090%2C%091%2C%0D%0A0%2C%091%2C%092%29


Solution set:
x%5B1%5D+=+1
x%5B2%5D+=+2