Question

{x ^ 2 - y ^ 2 = - 40;
{ x + y = 4​

Answer 1

Объяснение:

$x {}^{2} - y {}^{2} = - 40 \\ x + y = 4 \\ \\ x {}^{2} - y {}^{2} = - 40 \\ x = 4 - y \\ \\ (4 - y) {}^{2} - y {}^{2} = - 40 \\ y = 7 \\ \\ x = 4 - 7 \\ x = - 3 \\ \\ x = - 3 \\ y = 7$