Question

x+3/x-7-6/x+7=140/x^2-49 срочно помогите

Answer 1

$frac{x+3}{x-7}-frac6{x+7}=frac{140}{x^2-49}\\O.D.3.:\begin{cases}x-7neq0\x+7neq0\x^2-49neq0end{cases}Rightarrow xneqpm7\\frac{x+3}{x-7}-frac6{x+7}-frac{140}{(x-7)(x+7)}=0\frac{(x+3)(x+7)-6(x-7)-140}{(x-7)(x+7)}=0\x^2+10x+21-6x+42-140=0\x^2+4x-77=0\D=16-4cdot(-77)=16+308=324=(18)^2\x_{1,2}=frac{-4pm18}2\x_1=-11\x_2=7;-;He;nogx.;no;O.D.3.\OTBET:;x=-11$