Решить систему уравнений x+y=13 √ x+√ y=5 - вопрос №3337863135 от ybrybrybrybrrby 11.04.2022 20:07

Question

Алгебра: Решить систему уравнений x+y=13 √ x+√ y=5

ybrybrybrybrrby · Answer

X+y=13√ x+√ y=5x+y=13(√ x+√ y)^2 = 25x + y = 13x + y + 2√(xy) = 25x + y = 132√(xy) = 25 - 13x + y = `32√(xy) = 12x + y = 13√(xy) = 6x + y = 13xy = 36y = 13 - xx*(13 - x) = 36x^2 - 13x + 36 = 0D = 169 - 4*1*36 = 169 - 144 = 25x1 = (13 - 5)/2x1 = 8/2x1 = 4x2 = (13 + 5)/2x2 = 18/2x2 = 9y1 = 13 - 4y2 = 9y2 = 13 - 9 y2 = 4ответ: (4;9)  или (9;4)...