Question

400/x- 400/(x+10)=20

Hallar X

Answer 1

Solución:

400/x- 400/(x+10)=20

$\frac{400}{x}- \frac{400}{x+10}-20=0$

$\frac{400(x+10)-400x-20x(x+10)}{x(x+10)} =0$

$\frac{400x+4000-400x-20x²-200x}{x(x+10)}=0$

4000 - 20x² - 200x = 0

20(200 - x² - 10x) = 0

20( - x² - 10x + 200) = 0

20 ( -x (x-10) - 20( x-10) = 0

20 ( - (x-10)) (x + 20) = 0

-20 (x-10) ( x+20) = 0

x - 10 = 0

x + 20 = 0

x₁ = 10      x₂ = -20

Ufff no pensé que estaría tan larga jaja.

Saludos :D