second last move was 2 negatives on either side.Why or how is it all made positive. Is it just a custom or does it have an operation to achieve it.
Answer provided by our tutors
Multiplication property of equality states that if both the sides of an equation are multiplied by the same number, the expressions on the both sides of the equation remain equal to each other. So, in this case both sides are multiplied by (-1) and the final result is "X = 17"
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