Question

(x² - y² = 8,
x - y = 2.

Answer 1

a² - b² = (a - b)(a + b)

x² - y² = 8

x - y = 2

--

(x - y)(x + y) = 8

2(x + y) = 8

x - y = 4 и

x + y = 2

Складываем

2х = 6

x = 3

3 + y = 2

y = -1

ответ (3, -1)