Tìm x,y $\frac{x-y}{3}$ =$\frac{x+y}{15}$ =$\frac{x.y}{200}$ 08/07/2021 Bởi Savannah Tìm x,y $\frac{x-y}{3}$ =$\frac{x+y}{15}$ =$\frac{x.y}{200}$
$\frac{x-y}{3}$$=$$\frac{x+y}{15}$ $⇒$ $\frac{2x}{18}$ $=$ $\frac{xy}{200}$ $⇒400x=18xy$ $⇒400=18y$ $⇒y=$$\frac{200}{9}$ $Ta $ $có$ $\frac{x+y}{15}$ $=$ $\frac{xy}{200}$ $⇒$ $\frac{x+\frac{200}{9} }{15}$ $=$ $\frac{x}{9}$ $⇒$ $x=$ $\frac{100}{3}$ $Vậy$ $\left \{ {{x=\frac{100}{3}} \atop {y=\frac{200}{9}}} \right.$ Bình luận
Đáp án:
Đề em có sai không vậy??
$\frac{x-y}{3}$$=$$\frac{x+y}{15}$
$⇒$ $\frac{2x}{18}$ $=$ $\frac{xy}{200}$
$⇒400x=18xy$
$⇒400=18y$
$⇒y=$$\frac{200}{9}$
$Ta $ $có$ $\frac{x+y}{15}$ $=$ $\frac{xy}{200}$
$⇒$ $\frac{x+\frac{200}{9} }{15}$ $=$ $\frac{x}{9}$
$⇒$ $x=$ $\frac{100}{3}$
$Vậy$ $\left \{ {{x=\frac{100}{3}} \atop {y=\frac{200}{9}}} \right.$