Question

Tim x , y biết

1 \(\frac{x}{3}=\frac{y}{7}vàx^2+y^2=58\)

Answer 1

\(\frac{x}{3}=\frac{y}{7}=k\Leftrightarrow\frac{x^2}{9}=\frac{y^2}{49}=\frac{x^2+y^2}{9+49}=\frac{58}{58}=1=k^2\)

+k =1 => x =3 ; y =7

+k=-1 => x =-3; y=-7

 

 

Answer 2

=> \(\frac{x^2+y^2}{3^2+7^2}=\frac{58}{58}=1\)

=> x = 1 . 3 = 3

y = 1 . 7 = 7

KL:.........................