\(3,5.x+3,7.x+2,7=-7,8\)
\(\Leftrightarrow x\left(3,5+3,7\right)+2,7=-7,8\)
\(\Leftrightarrow7,2x+2,7=-7,8\)
\(\Leftrightarrow7,2x=-10,5\)
\(\Leftrightarrow x=\frac{-35}{24}\)
Vậy x = -35/24
\(b,-7,2x+3,7x+2,7=-7,8\)
\(\Leftrightarrow x\left(-7,2+3,7\right)+2,7=-7,8\)
\(\Leftrightarrow-3,5x+2,7=-7,8\)
\(\Leftrightarrow-3,5x=-10,5\)
\(\Leftrightarrow x=3\)
Vậy x =3