Đáp án:
$\dfrac{5y^2-6x^2+7xy}{3x^2-10y^2+xy}=-\dfrac{y+2x}{x+2y}$
Giải thích các bước giải:
$\dfrac{5y^2-6x^2+7xy}{3x^2-10y^2+xy}$
$=\dfrac{5y^2-3xy+10xy-6x^2}{3x^2-5xy+6xy-10y^2}$
$=\dfrac{(5y-3x)(y+2x)}{(3x-5y)(x+2y)}$
$=-\dfrac{(3x-5y)(y+2x)}{(3x-5y)(x+2y)}$
$=-\dfrac{y+2x}{x+2y}$