Question

the sum of a two digit number is 12 the number obtained by interchanging the exceeds 18

Answer 1

Substitute the value of y from eqn 1 in eqn 2

12 – x – x = 2

12 – 2x = 2

2x = 10

x = 5

Therefore, y = 12 – x = 12 – 5 = 7

Therefore, the two-digit number is 10x + y = (10*5) + 7 = 57
    

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Answer 2

here is your answer my friend
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