Question 470851
let the two numbers be x and x-5 

(x)^2 + (x-5)^2 = 125
 x^2 + x^2 + 25 -10x =125
 2x^2 - 10x +25 =125
 2x^2 -10x= 125-25
 2x^2 -10x =100
 2x(x-10) = 100
  x(x-10) = 100/2
  x(x-10)=50
  x^2-10x-50 = 0
  x^2 -10x +5x -50 =0
  x(x-10) +5(x-10) =0
 (x+5)(x-10) = 0
(x+5) = 0   ; (x-10)=0
x= -5      ; x=10

so the two numbers be -5 and 10

Counter check 
 (-5)^2 + (10)^2
=  25+100
= 125