use quadratic formula to solve :
x2+2ax+(a 2 -b2)=0
x2 - 2ax + (a2 - b2) = 0
x2 - 2ax + (a + b)(a - b) = 0
x2 - (a - b)x - (a + b)x + (a + b)(a - b) = 0
x(x - a + b) - (a + b)(x - a + b) = 0
(x - a + b)(x - a - b) = 0
x = a + b , x = a - b
use quadratic formula to solve :
x2+2ax+(a 2 -b2)=0
x2 - 2ax + (a2 - b2) = 0
x2 - 2ax + (a + b)(a - b) = 0
x2 - (a - b)x - (a + b)x + (a + b)(a - b) = 0
x(x - a + b) - (a + b)(x - a + b) = 0
(x - a + b)(x - a - b) = 0
x = a + b , x = a - b