a) Chứng minh rằng nếu 2(x+y)  = 5(y+z) = 3(z+x) 

Thì \(\dfrac{x-y}{4}=\dfrac{y-z}{5}\) 

b) Cho \(x^2=yz\)  . Chứng minh rằng \(\dfrac{x^2+y^2}{y^2+z^2}=\dfrac{x}{z}\) 

Cho \(\dfrac{x}{3}=\dfrac{y}{4}=\dfrac{z}{11}\) . Tính giá trị của \(A=\dfrac{y+z-x}{x+z-y}\) 

1.Reorder the following words to make meaningful sentences 

she/in/ close / watching / her / is / movies / friends / at / interested / cinema / the /with . 

2. Rewrite the following sentences based on the given words 

1. My friend is a big fan of K-pop music .

=> My friend is  ............................................ (fond)

Tìm x biết : \(\left|x^4+x^2+1\right|=x^2-x+1\)