Question

Giải phương trình:

a) \(\dfrac{5x+3}{2}\) + \(\dfrac{3x-8}{4}\) = 4

b) \(\dfrac{5x-6}{3}\) - \(\dfrac{5x+6}{12}\) = 1

Answer 1

a) Ta có: \(\dfrac{5x+3}{2}+\dfrac{3x-8}{4}=4\)

\(\Leftrightarrow\dfrac{2\left(5x+3\right)}{4}+\dfrac{3x-8}{4}=4\)

\(\Leftrightarrow10x+6+3x-8=16\)

\(\Leftrightarrow13x-2=16\)

\(\Leftrightarrow13x=18\)

hay \(x=\dfrac{18}{13}\)

Vậy: \(x=\dfrac{18}{13}\)

b) Ta có: \(\dfrac{5x-6}{3}-\dfrac{5x+6}{12}=1\)

\(\Leftrightarrow\dfrac{4\left(5x-6\right)}{12}-\dfrac{5x+6}{12}=1\)

\(\Leftrightarrow20x-24-5x-6=12\)

\(\Leftrightarrow15x-30=12\)

\(\Leftrightarrow15x=42\)

hay \(x=\dfrac{14}{5}\)

Vậy: \(x=\dfrac{14}{5}\)