There are several ways to solve a system of equation; one of these ways is the use of matrix.
<em>Jerry made a mistake at step 2</em>
From the attachment, the step 1 is represented as:
The equation in step 2 is given as:
This means that:
We subtract the elements of row 2 from the elements of row 1, multiplied by 5
So, we have:
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Subtract corresponding cells
So, the new row 2 elements should be:
However, the row 2 elements of Jerry's steps are:
This means that:
Jerry made a mistake; and the mistake is at step 2
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