2.08813781251 nhé

\(\frac{4}{5}\)+ \(\frac{1}{5}\): \(\frac{-2}{15}\)= \(\frac{4}{5}\)+ \(\frac{1}{5}\)* \(\frac{-15}{2}\)=\(\frac{4}{5}\) + \(\frac{-3}{2}\)= \(\frac{-7}{10}\)

b = \(\frac{-7}{12}\). (\(\frac{3}{11}\)+ \(\frac{-14}{11}\)) + \(\frac{5}{6}\)= \(\frac{-7}{12}\). (-1) + \(\frac{5}{6}\)= \(\frac{7}{12}\)+ \(\frac{10}{12}\)= \(\frac{17}{12}\)

x-\(\frac{3}{5}\)x = \(\frac{2}{5}\)

=> x.(1-\(\frac{3}{5}\)) =\(\frac{2}{5}\)

=> x. \(\frac{2}{5}\)= \(\frac{2}{5}\)

=> x=1

Vậy x=1

\(a.\frac{8}{7}+\frac{4}{7}\times\left(-\frac{6}{11}\right)-\frac{4}{7}\times\frac{5}{11}\)

\(=\frac{8}{7}+\frac{4}{7}\left(-\frac{6}{11}-\frac{5}{11}\right)\)

\(=\frac{8}{7}+\frac{4}{7}.\left(-1\right)\)

\(=\frac{8}{7}-\frac{4}{7}\)

\(=\frac{4}{7}\)

\(\left(6:3,5-1\dfrac{1}{6}\times\dfrac{6}{7}\right):\left(4,2\times\dfrac{10}{11}+5\dfrac{2}{11}\right)\\ =\left(\dfrac{12}{7}-\dfrac{7}{6}\times\dfrac{6}{7}\right):\left(\dfrac{21}{5}\times\dfrac{10}{11}+\dfrac{57}{11}\right)\\ =\left(\dfrac{17}{7}-1\right):\left(\dfrac{42}{11}+\dfrac{57}{11}\right)\\ =\dfrac{10}{7}:9\\ =\dfrac{10}{63}\)

\(\left(6:\dfrac{3}{5}-1\dfrac{1}{6}\times\dfrac{6}{7}\right):\left(4,2\times\dfrac{10}{11}+5\dfrac{2}{11}\right)\)

\(=\left(6\times\dfrac{5}{3}-\dfrac{7}{6}\times\dfrac{6}{7}\right):\left(\dfrac{21}{5}\times\dfrac{10}{11}+\dfrac{57}{11}\right)\)

\(=\left(10-1\right):\left(\dfrac{42}{11}+\dfrac{57}{11}\right)=9:9=1\)

Một hình thang có hiệu hai đáy là 18 cm, đáy bé bằng 3/5 đáy lớn, đáy lớn bằng 3/2 chiều cao. Tình diện tích của hình thang đó ?

Hỡi các thiên tài toán học, hãy giải giúp mình bài toán này !

                                                                                Trân trọng cảm ơn !

các bn lm đến đâu cx dc miễn là lm hộ mk cái ạ, ai đang lm vào nhắn tin vs mk để mk bít nha

a; \(-\dfrac{8}{3}+\dfrac{7}{5}-\dfrac{71}{15}< x< -\dfrac{13}{7}+\dfrac{19}{14}-\dfrac{7}{2}\)

              -\(\dfrac{19}{15}\) - \(\dfrac{71}{15}\) < \(x\) < -\(\dfrac{1}{2}\) - \(\dfrac{7}{2}\)

              -6 < \(x\) < -4

             vì \(x\) \(\in\) Z nên \(x\) = -5

- \(\dfrac{19}{6}+\dfrac{-15}{2}+\dfrac{11}{3}\) < \(x\) < - \(\dfrac{5}{4}\) + \(\dfrac{19}{12}\) - \(\dfrac{10}{3}\)

- \(\dfrac{32}{3}+\dfrac{11}{3}< x< \) \(\dfrac{1}{3}\) - \(\dfrac{10}{3}\)

-7 < \(x\) < - 3

Vì \(x\in\) Z nên \(x\in\) {-6;-5;-4}

[6: 3/5 - 7/6 x 6/7] : [ 21/5 x 10/11 + 57/11]

= 9 : 9

= 1 

\(\left(6:\frac{3}{5}-\frac{7}{6}\times\frac{6}{7}\right):\left(\frac{21}{5}\times\frac{10}{11}+\frac{57}{11}\right)\)

\(=\left(10-1\right):\left(\frac{42}{11}+\frac{57}{11}\right)\)

\(=9:9\)

\(=1\)

\(\left(6\div\frac{3}{5}-\frac{7}{6}\times\frac{6}{7}\right)\div\left(\frac{21}{5}\times\frac{10}{11}+\frac{57}{11}\right)\)

\(=\left(6\times\frac{5}{3}-1\right)\div\left(\frac{42}{11}+\frac{57}{11}\right)\)

\(=\frac{13}{5}\div9\)

\(=\frac{13}{45}\)

\(\dfrac{5}{7}\cdot\dfrac{6}{11}+\dfrac{5}{11}\cdot\dfrac{1}{7}-\dfrac{5}{7}\cdot\dfrac{14}{11}\)

\(=\dfrac{5}{7}\cdot\dfrac{6}{11}+\dfrac{5}{7}\cdot\dfrac{1}{11}-\dfrac{5}{7}\cdot\dfrac{14}{11}\)

\(=\dfrac{5}{7}\cdot\left(\dfrac{6}{11}+\dfrac{1}{11}-\dfrac{14}{11}\right)\)

\(=\dfrac{5}{7}\cdot\dfrac{-7}{11}=\dfrac{-5}{11}\)