Bài 1: tìm x , y nguyên bt
a) $\frac{-5}{x}$ = $\frac{y}{16}$ = $\frac{3}{z}$ = $\frac{-18}{72}$
b) $\frac{x + 2 }{-5}$ = $\frac{y - 3 }{-4}$ = $\frac{2-z}{-6}$ = $\frac{24}{18}$
Bài 2 : Tính
a) $\frac{-5}{x}$ + ( 2 + $\frac{5}{17}$ )
b) ( $\frac{3}{7}$ + $\frac{4}{9}$ ) + $\frac{-4}{9}$
c) $\frac{3}{17}$ + $\frac{-5}{13}$ + $\frac{14}{17}$ + $\frac{-8}{3}$
d) $\frac{6}{11}$ + $\frac{4}{-9}$ + $\frac{2}{11}$ + $\frac{-5}{9}$ + $\frac{3}{11}$
Loga
Sinh Học lớp 12
