Question

The sum of two numbers is 128 and their difference is 16. Find the numbers.

Answer 1

Let the two numbers be x and y 

According to 1^st condition ,

x+y=128  ------{1}

According to 2nd condition ,

x-y=16 --------{2}

Adding equation 1 and 2

   x+y=128

+ x-y=16

---------------------------

2x=144

x=72

put x=72 in first equation , 

72+y=128

y=128-72=56

y=56 

Hence , the first numbers are 72 and 56