\(\Leftrightarrow\dfrac{a}{b}\cdot\dfrac{3}{4}=\dfrac{8}{5}\)
hay a/b=32/15
\(\dfrac{3a}{4b}+\dfrac{2}{5}=2\Leftrightarrow\dfrac{3a}{4b}=2-\dfrac{2}{5}=\dfrac{8}{5}\Leftrightarrow\dfrac{a}{b}=\dfrac{8}{5}:\dfrac{3}{4}=\dfrac{32}{15}\)
a/b x 3/4 +2/5 =2
a/b x 3/4 =2-2/5
a/b x3/4 =8/5
a/b =8/5 : 3/4
a/b =32/15