Bài 1 a, -2/5 + -5/4 . 8/3 + 8/15 b, x .2/5 = -5 /4 05/12/2021 Bởi Maria Bài 1 a, -2/5 + -5/4 . 8/3 + 8/15 b, x .2/5 = -5 /4
a) $\frac{-2}{5}$ + $\frac{-5}{4}$ . $\frac{8}{3}$ + $\frac{8}{15}$ = $\frac{-2}{5}$ + $\frac{-10}{3}$ + $\frac{8}{15}$ = $\frac{-56}{15}$ + $\frac{8}{15}$ = $\frac{-16}{5}$ = -3$\frac{1}{5}$ b) x . $\frac{2}{5}$ = $\frac{-5}{4}$ x = $\frac{-5}{4}$ : $\frac{2}{5}$ x = $\frac{-25}{8}$ = -3$\frac{1}{8}$ Bình luận
a) `-2/5 + (-5/4). 8/3 + 8/15` `= -2/5 + (-10/3) + 8/15` `= -56/15 + 8/15` `= -16/5` b) `x. 2/5 = -5/4` `⇒ x = -5/4 : 2/5` `⇒ x = -25/8` Bình luận
a) $\frac{-2}{5}$ + $\frac{-5}{4}$ . $\frac{8}{3}$ + $\frac{8}{15}$
= $\frac{-2}{5}$ + $\frac{-10}{3}$ + $\frac{8}{15}$
= $\frac{-56}{15}$ + $\frac{8}{15}$
= $\frac{-16}{5}$ = -3$\frac{1}{5}$
b) x . $\frac{2}{5}$ = $\frac{-5}{4}$
x = $\frac{-5}{4}$ : $\frac{2}{5}$
x = $\frac{-25}{8}$ = -3$\frac{1}{8}$
a) `-2/5 + (-5/4). 8/3 + 8/15`
`= -2/5 + (-10/3) + 8/15`
`= -56/15 + 8/15`
`= -16/5`
b) `x. 2/5 = -5/4`
`⇒ x = -5/4 : 2/5`
`⇒ x = -25/8`