1. Tính giá trị biểu thức:
\(A=-1,6:\left(1+\frac{2}{3}\right)\)
\(B=1,4.\frac{15}{49}-\left(\frac{4}{5}+\frac{2}{3}\right):2\frac{1}{5}\)
2. Tìm x:
a, \(\left(2,8x-32\right):\frac{2}{3}=-90\)
b, \(\left(4,5-2x\right).1\frac{4}{7}=\frac{11}{14}\)