c: =13x29=377

b

A 24/3 nhá bạn 

24 : 3=........=..........

a.24/3          b.8          c.9

A

A

\(840=2^3\times3\times5\times7\)

\(150=2\times3\times5^2\)

\(990=2\times3^2\times5\times11\)

ƯCLN(840;150;990)=\(2\times3\times5=30\)

Vì \(\overline{2x7y}⋮2;5\) nên \(y=0\)

Vì \(\overline{2x7y}⋮3;9\) nên \(\overline{2x70}⋮9\)

\(\Rightarrow2+x+7+0⋮9\\ \Rightarrow x+9⋮9\\ \Rightarrow x\in\left\{0;9\right\}\)

Vậy các số cần tìm là \(2070;2970\)

???

bn ơi???

x = 0

y = 0

Đáp án:

X =0 hoặc x=9

y=0 

\(-\dfrac{2}{3}=\dfrac{x}{-6}\Rightarrow x=\left(-\dfrac{2}{3}\right)\left(-6\right)=4\)

\(-\dfrac{2}{3}=\dfrac{10}{-y}\Rightarrow y=\left(-10\right):\left(-\dfrac{2}{3}\right)=15\)

\(-\dfrac{2}{3}=\dfrac{z}{9}\Rightarrow z=\left(-\dfrac{2}{3}\right).9=-6\)

\(\dfrac{-2}{3}=\dfrac{x}{-6}=\dfrac{10}{-y}=\dfrac{z}{9}\)

\(x=\left(-6.-2\right):3=4;y=\left(-6.10\right):-4=15;z=\left(10.9\right):-15=-6\)