Question

-1/2.3x+3/4=-2,25

Answer 1

-1/2.3x+3/4=-2.25

-1/2.3x+3/4=9/4

-1/2.3x      =9/4-3/4

-1/2.3x      =3/2

       3x     =3/2:-1/2

       3x     =-3

        x     =-3:3

        x     =-1

vậy   x=-1

Answer 2

\(-\frac{1}{2}.3x+\frac{3}{4}=-2,25\)

\(\Rightarrow\frac{1}{2}.(-3).x+\frac{1}{2}.\frac{3}{2}=\frac{9}{4}\)

\(\Rightarrow\frac{1}{2}.\left(-3x+\frac{3}{2}\right)=\frac{9}{4}\)

\(\Rightarrow-3x+\frac{3}{2}=\frac{9}{4}:\frac{1}{2}\)

\(\Rightarrow-3x+\frac{3}{2}=\frac{9}{2}\)

\(\Rightarrow-3x=3\)

\(\Rightarrow x=-1\)