\(\left(-5,6\right)\cdot x+2,9\cdot x-3,86=-9,8\)
\(=x\left(-5,6+2,9\right)-3,86=-9,8\)
\(=x\cdot\left(-2,7\right)-3,86=-9,8\)
\(\Rightarrow x\cdot\left(-2,7\right)=-9,8+3,86=-5,94\)
\(\Rightarrow x=-5,94:\left(-2,7\right)=2,2\)
\(\Rightarrow x=2,2\)