5x+2y=100. lg x - lg y = lg 16-1
Lg x - lg y = lg 16 - 1 = lg 16 - lg 10 lg (x/y) = lg (16/10) = lg (8/5) x/y = 8/5 x = 8y/5 Подставляем в 1 уравнение 5*8y/5 + 2y = 100 8y+2y=10y=100 y=100/10=10 x=8y/5=80/5=16