Question

$left { {{x+y=7} atop {lg x + lg y=1}} right.$

Помогите.

Answer 1

x + y = 7
lg (xy) = 1
x > 0
y > 0

x + y = 7
xy = 10
x > 0
y > 0

x = 2, y = 5
x = 5, y = 2

Ответ: (2; 5), (5; 2).