The difference between two numbers is 26 and one number is three times the other. Find them

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3. Form the pair of linear equations for the following problems and find their solution by substitution    method.

(i) The difference between two numbers is 26 and one number is three times the other. Find them

Solution: 

Let be numbers = x, y

difference between two numbers is 26

 x-y=26--------(1)

 One number is three times the other

 x=3y-------(2)

 substitute x=3y in equation (1)

  x-y=26

 3y-y=26

 2y=26

 y=13

 substitute y=13 in equation (2)

 x=3y

 x=3x13=39

 x=39, y=13

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