# Magic square with equal sums on rows, columns and diagonals

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Transcription:

In a given magic square, if the sum of number in each row
and each column and both of the main diagonals are equal,
then the value of x is:

1) 10
2) 12
3) 8
4) 15


• Is this question from an ongoing competition? If not, credit the source. – Maria Deleva Feb 4 '17 at 17:46

$$13+y+d=15+y+5 \implies d=7$$
$$b+15+d=x+y+b \implies x+y=22$$ (using d=7) $$13+5+x=15+5+y \implies x-y=2$$