Tìm x:
a) (2,8x - 32) :\(\frac{2}{3}\)=90
b) 4,5 - 2x . \(1\frac{4}{7}\)=\(\frac{11}{14}\)
c) (x+ \(\frac{1}{4}-\frac{1}{3}\) ): (2+\(\frac{1}{6}-\frac{1}{4}\))=\(\frac{7}{46}\)
d)\(\frac{13}{15}-\left(\frac{13}{21}+x\right).\frac{7}{12}=\frac{7}{10}\)
\(\left(2.8x-32\right):\frac{2}{3}=90\)
\(2.8\cdot x-32=90\cdot\frac{2}{3}\)
\(\frac{14}{5}x-32=60\)
\(\frac{14}{5}x=60+32\)
\(\frac{14}{5}x=92\)
\(x=\frac{230}{7}\)
B , c , d tương tự