Problema Solution

When you reverse the digits in a certain two-digit number you decrease it's value by 45.Find the number if the sum of it's digits is 5.

Answer provided by our tutors

let


x = the unit digit


y = the tens digit


the two digit number is: x + 10y


when you reverse the digits you get the number: y + 10x


when you reverse the digits in a certain two-digit number you decrease it's value by 45:


y + 10x = x + 10y - 45


the sum of it's digits is 5:


x + y = 5


by solving the system of equations:


y + 10x = x + 10y - 45


x + y = 5


we find:


x = 0


y = 5


click here to see the step by step solution of the system of equations:


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the number is: 0 + 5*10 = 50.