Question

решите систему log_3( x+y)=2 9^log_3/x-y=5

Answer 1

$left { {{log_3(x+y)=2} atop {9^{log_3 sqrt{x-y} }=5}} right. to left { {{log_3(x+y)=log_33^2} atop {3^{2log_3 sqrt{x-y}}=5 }} right. to left { {{x+y=9} atop {x-y=5}} right.$
Прибавим уравнения
2x=14
x=7
y=2

Ответ: (7;2)