Question

\(\frac{21}{x}\)=\(\frac{y}{16}\)=\(\frac{-14}{z}\)=\(\frac{7}{4}\)                                          \(\frac{-21}{x}\)=\(\frac{y}{-16}\)=\(\frac{81}{z}\)=\(\frac{-3}{4}\)

Answer 1

chị tho ruby trả lời em cho 1 k

Answer 2

\(\frac{21}{12}=\frac{28}{16}=\frac{-14}{-8}=\frac{7}{4}\)

\(\frac{-21}{28}=\frac{12}{-16}=\frac{81}{-108}=\frac{-3}{4}\)

Answer 3

Nhân chéo chia ngang nha

Vd:

\(\frac{a}{b}=\frac{c}{d}\)

=> a = \(\frac{c.b}{d}\)

=> b = \(\frac{a.d}{b}\)

=> c = \(\frac{a.d}{b}\)

=> d = \(\frac{b.c}{a}\)