уравнение. Помогите решить ((x+4) / (x-5)) + (x/ (x+5)) =50 / (x^2-25)

Question

Александр · Accepted Answer

Ответ 
 ((x+4) / (x-5)) + (x/ (x+5)) =50 / (x^2-25) 
 ((x+4) / (x-5)) + (x/ (x+5)) =50 / {(x+5)(x-5)} 
(x+4)(x+5) + x*(x-5) = 50 
x^2 + 4x + 5x + 20 + x^2 - 5x = 50 
2x^2 + 4x - 30 = 0 
x^2 + 2x - 15 = 0 
x(1,2) = [-2 +- V{(-2)^2 + 4*15] /2 = 
= (-2 +- V64) /2 = 
= (-2 +- 8) /2 = -1 +- 4 
x(1) = -1 + 4 = 3 
x(2) = -1 - 4 = -5