Answer:
and the mistake was in calculating let's solve first.
Step-by-step explanation:
if , substitute the in the equation as
solve the equation in parentheses :
multiply by it will equal to:
now we want to let all unknown digits alone, so we will take to the other side with a different sign it will be as:
now we will solve it:
at this part, the given equation was wrong in the paper.
we don't want the digit to be negative so we will do it like this:
now that we found we will substitute it to find :
overall the mistake was in calculating instead of putting
he/she put a different sign in front of the digit like :
so when he/she flipped it became positive and instead of subtracting he/she added it.