Como factorizar (x + y)² - 2(x + y)(x + a) + (a + x)²?

Respuesta : Explicación paso a paso : <img src="https://tex.z-dn.net/?f=%5Ctexttt%7BLa%20expresi%5C%27on%20es%3A%7D%5C%5C%5C%5C%28x%2By%29%5E%7B2%7D-2%28x%2By%29%28a%2Bx%29%2B%28a%2Bx%29%5E%7B2%7D%5C%5C%5Ctexttt%7BSe%20puede%20ver%20facilmente%2C%20que%20es%20un%20trinomio%20cuadrado%20perfecto%7D%5C%5C%5Ctexttt%7Bes%20decir%20puede%20factorizarze%20en%20la%20forma%3A%7D%5C%5C%5C%5Ca%5E%7B2%7D-ab%2Bb%5E%7B2%7D%3D%28a-b%29%5E%7B2%7D%5C%5C%5Ctexttt%7BPor%20lo%20tanto%2C%20haciendo%7D%5C%2C%5C%2Ca%5E%7B2%7D%3D%28x%2By%29%5E%7B2%7D%5C%2C%5C%2Cb%5E%7B2%7D%3D%28a%2Bx%29%5E%7B2%7D%5C%2C%5Ctexttt%7Bse%20obtiene%3A%7D%5C%5C%5C%5C%5Csqrt%7B%28x%2By%29%5E%7B2%7D%7D%3Dx%2By%5C%5C%5Csqrt%7B%28a%2Bx%29%5E%7B2%7D%7D%3Da%2Bx%5C%5C2%28x%2By%29%28a%2Bx%29%5C%5C%28x%2By%29%5E%7B2%7D-2%28x%2By%29%28a%2Bx%29%2B%28a%2Bx%29%5E%7B2%7D%3D%28%28x%2By%29-%28a%2Bx%29%29%5E%7B2%7D" />.