Question

AJUDAAAAAAAAAAAAAAA GEOMETRIA PLANA??
DETERMINE X E Y,SENDO R,S E T RETAS PARALELAS.

Answer 1

$\frac{x}{x-7} = \frac{12-x}{2}$

$(x-7)(12-x)=2x$

$12x- x^{2} +84+7x=2x$

$12x- x^{2} +84+7x-2x=0$

$- x^{2} +17x+84=0$

$x^{2} -17x-84=0$

$x= \frac{17\pm \sqrt{17^2+336} }{2}$

$x= \frac{17\pm \sqrt{625} }{2}$

$x= \frac{17\pm25}{2}$

$x'= \frac{17+25}{2} = \frac{42}{2} =21$

$\fbox{ x=21 }$


$\frac{2}{14} = \frac{20-y}{y}$

$280-14y=2y$

$-14y-2y=-280$

$-16y=-280$

$16y=280$

$y= \frac{280}{16} = \frac{35}{2} =17,5$

$\fbox{ y=17,5 }$