Question

the sum of two rational number is 58 and the difference is 28. find the number

Answer 1

let the two rational numbers be x and y
therefore x + y = 58
and        x - y = 28
adding the two equations we get that 2x = 86 and thus x = 43 
and thus y = 15

x = 43 and y = 15

Answer 2

Let first rational no. be x
the second no. be y
A/q
    x + y = 58 .............(i)
    x -  y = 28 .............(ii)
On adding eq. (i) and (ii), we get
    x + y = 58 
    x -  y = 28 
   2x      =  86
    x = 86/2 = 43
Now substituting the value of x= 43 in eq. (i)
x + y = 58
43 + y = 58
y = 58 - 43
y = 15
Therefore the two rational numbers are 43 and 15