Respuesta :

9514 1404 393

Answer:

  a-b

Step-by-step explanation:

Add the two equations together:

  (ax +by) +(bx +ay) = (a² -b²) +(0)

  x(a +b) +y(a +b) = (a +b)(a -b)

  x + y = a - b . . . . . divide by (a+b), assuming a+b ≠ 0