e, Tìm x

\(\dfrac{3-x}{12}=\dfrac{192}{-72}\)

\(\left(3-x\right).\left(-72\right)=192.12\)

\(-216+72x=2304\)

\(72x=2304-\left(-216\right)=2520\)

\(x=2520:72\)

\(x=35\)

Tìm y

\(\dfrac{3-35}{12}=\dfrac{16}{y+1}\)

\(\dfrac{-32}{12}=\dfrac{16}{y+1}\)

\(\dfrac{-8}{3}=\dfrac{16}{y+1}\)

\(\left(-8\right).\left(y+1\right)=16.3\)

\(-8y+\left(-8\right)=48\)

\(-8y=48-\left(-8\right)=56\)

\(y=56:\left(-8\right)\)

\(y=-7\)

f,Tim x

\(\dfrac{-\left(x+3\right)}{27}=\dfrac{-121}{33}\)

\(\dfrac{-\left(x+3\right)}{27}=\dfrac{-11}{3}\)

\(-\left(x+3\right).3=\left(-11\right).27\)

\(-x.3+\left(-3\right).3=-297\)

\(-3x+\left(-9\right)=-297\)

\(-3x=\left(-297\right)-\left(-9\right)=-288\)

\(x=\left(-288\right):\left(-3\right)\)

\(x=96\)

Tìm y

\(\dfrac{-\left(96+3\right)}{27}=\dfrac{11}{1-2y}\)

\(\dfrac{-99}{27}=\dfrac{11}{1-2y}\)

\(\dfrac{-11}{3}=\dfrac{11}{1-2y}\)

\(\left(-11\right).\left(1-2y\right)=11.3\)

\(\left(-11\right)-2y.\left(-11\right)=33\)

\(2y.\left(-11\right)=\left(-11\right)-33=-44\)

\(2y=\left(-44\right):\left(-11\right)=4\)

\(y=4:2\)

\(y=2\)

Câu e và câu f mik lúc nãy chx lm đuợc giờ giửi cho bạn 2 cây này

where 

who

\(a,x=\dfrac{-3}{4}-\dfrac{-2}{3}\)

\(x=\dfrac{-9}{12}-\dfrac{-8}{12}\)

\(x=\dfrac{-1}{12}\)

\(b,\dfrac{-3}{4}+\dfrac{1}{4}x=\dfrac{-8}{8}+\dfrac{7}{8}=\dfrac{-1}{8}\)

\(\dfrac{1}{4}x=\dfrac{-1}{8}-\dfrac{-3}{4}\)

\(\dfrac{1}{4}x=\dfrac{-1}{8}-\dfrac{-6}{8}=\dfrac{5}{8}\)

\(x=\dfrac{5}{8}:\dfrac{1}{4}=\dfrac{5}{8}.\dfrac{4}{1}\)

\(x=\dfrac{20}{8}=\dfrac{5}{2}\)

\(c,3.2^{2x+1}=\dfrac{49}{2}-\dfrac{1}{2}=24\)

\(2^{2x+1}=24:3=8\)

\(2^{2x+1}=2^3\)

\(2x+1=3\)

\(2x=3-1=2\)

\(x=2:2\)

\(x=1\)

\(d,\dfrac{5}{2}-3.\left(x+\dfrac{4}{3}\right)=\dfrac{3}{2}\)

\(3.\left(x+\dfrac{4}{3}\right)=\dfrac{5}{2}-\dfrac{3}{2}=1\)

\(x+\dfrac{4}{3}=1:3=\dfrac{1}{3}\)

\(x=\dfrac{1}{3}-\dfrac{4}{3}\)

\(x=\dfrac{-3}{3}=-1\)

Cái này giống kiểu đố mẹo như 1+ 1 = 3 đúng ko

\(8.\dfrac{-3}{7}+\left(3-\dfrac{3}{4}\right)-\left(\dfrac{9}{4}-\dfrac{10}{7}\right)=8.\dfrac{-3}{7}+\left(\dfrac{12}{4}-\dfrac{3}{4}\right)-\left(\dfrac{63}{28}-\dfrac{40}{28}\right)=8.\dfrac{-3}{7}+1-\dfrac{23}{28}=\dfrac{-24}{7}+1-\dfrac{23}{28}=\dfrac{-96}{28}+\dfrac{28}{28}-\dfrac{23}{28}=\dfrac{-91}{28}=\dfrac{-13}{4}\)

\(a,\dfrac{92}{9}+\dfrac{12}{5}-\dfrac{56}{9}=\dfrac{460}{45}+\dfrac{108}{45}-\dfrac{280}{45}=\dfrac{288}{45}=\dfrac{32}{5}\)

\(b,\dfrac{68}{7}-\left(\dfrac{41}{9}+\dfrac{30}{7}\right)=\dfrac{68}{7}-\left(\dfrac{287}{63}+\dfrac{270}{63}\right)=\dfrac{68}{7}-\dfrac{557}{63}=\dfrac{612}{63}-\dfrac{557}{63}=\dfrac{55}{63}\)

\(c,\dfrac{14}{3}+\dfrac{11}{4}.\dfrac{85}{11}=\dfrac{14}{3}+\dfrac{85}{4}=\dfrac{56}{12}+\dfrac{255}{12}=\dfrac{311}{12}\)

\(d,\dfrac{41}{8}-\dfrac{7}{4}:\dfrac{11}{5}=\dfrac{41}{8}-\dfrac{7}{4}.\dfrac{5}{11}=\dfrac{41}{8}-\dfrac{35}{44}=\dfrac{451}{88}-\dfrac{70}{88}=\dfrac{381}{88}\)

\(-\dfrac{1}{2}-x=\dfrac{2}{3}-\dfrac{-4}{5}\)

\(\dfrac{-1}{2}-x=\dfrac{10}{15}-\dfrac{-12}{15}=\dfrac{22}{15}\)

\(x=\dfrac{-1}{2}-\dfrac{22}{15}\)

\(x=\dfrac{-15}{30}-\dfrac{44}{30}\)

\(x=\dfrac{-59}{30}\)

câu a ko tính đc x

\(b,\dfrac{2}{9}.x=\dfrac{7}{9}-\dfrac{4}{3}=\dfrac{7}{9}-\dfrac{12}{9}=\dfrac{-5}{9}\)

\(x=\dfrac{-5}{9}:\dfrac{2}{9}\)

\(x=\dfrac{-6}{9}.\dfrac{9}{2}=\dfrac{-54}{18}=-3\)

\(c,\dfrac{3}{10}-x=\dfrac{-2}{5}:\dfrac{-1}{3}=\dfrac{-2}{5}.\dfrac{3}{-1}=\dfrac{-6}{-5}=\dfrac{6}{5}\)

\(x=\dfrac{3}{10}-\dfrac{6}{5}=\dfrac{3}{10}-\dfrac{12}{10}=\dfrac{-9}{10}\)

\(d,\dfrac{1}{3}:x=\left(-7\right)-\dfrac{1}{3}=\dfrac{-21}{3}-\dfrac{1}{3}=\dfrac{-22}{3}\)

\(x=\dfrac{1}{3}:\dfrac{-22}{3}=\dfrac{1}{3}.\dfrac{3}{-22}=\dfrac{3}{-66}=\dfrac{-1}{22}\)