Cho mk ctlhn nhé!
a, $\frac{3}{4}$ ×(x+1) = $\frac{4}{5}$
⇔ x+1= $\frac{4}{5}$ ÷ $\frac{3}{4}$
⇔ x+1= $\frac{16}{15}$
⇔ x= $\frac{16}{15}$ - 1 = $\frac{1}{15}$
Vậy x= $\frac{1}{15}$
b, $\frac{1}{8}$ ÷ (x-1)= $\frac{1}{4}$
⇔ x-1 = $\frac{1}{8}$ ÷ $\frac{1}{4}$
⇔ x-1 = $\frac{1}{2}$
⇔ x = $\frac{1}{2}$ +1 = $\frac{3}{2}$
Vậy x = $\frac{3}{2}$