Anonymous

cotx+coty=5 => 1/tanx+1/tany=5 => (tanx+tany)/(tanxtany)=5 => tanxtany=4/5 => tan(x+y)=4/(1-4/5)=20

Anonymous

tan x + tan y = 4 cot x + cot y = 5 1/tan x + 1/ tan y = 5 tan x + tan y = 5 tan x tan y 4 = 5 tan x tan y tan x tan y = 4/5 tan(x + y) = tan(tan^(-1)(2 - 4/sqrt(5)) + tan^(-1)(2 + 4/sqrt(5))) = 20

Anonymous

1/tanx + 1/tany = 5 (tanx + tany)/(tanxtany) = 5 tanxtany = 4/5 tan(x+y) = 4/(1-4/5) = 20

Anonymous

tan(x+y) cot x+ cot y= 1/tan x+1/tan y= (tan x +tan y)/(tan xTan y)= 4/(tanx tany)=5 tan x tan y= 4/5 tan (x+y) = (tanx +tany)/(1-tan x tany)= 4/(1-4/5)=20 Please check the answer.