Question

ПОЖАЛУЙСТА РЕШИТЕ СИСТЕМУ

Answer 1

$(x + 2y)(x - 2y) = 9 \ y(x + 2y) = 3 \ \ \ \ (x + 2y)(x - 2y) = 9 \ 3y(x + 2y) = 9 \ \ \ 3y = x - 2y \ \ x = 5y \ \7y times 3y = 9 \ 21 {y}^{2} = 9 \ {y}^{2} = frac{9}{21} \ sqrt{ {y}^{2} } = sqrt{ frac{9}{21} } = frac{3}{ sqrt{21} } \ |y| = frac{3}{ sqrt{21} } \ y = + - frac{3}{ sqrt{21} } \ \ \ x = + - frac{15}{ sqrt{21} }$

Знаки либо - и - , либо + и +.