hello
the equation given is
[tex]-\frac{1}{3}(2.7d+1.8)=(xd-0.6)[/tex]let's resolve both sides of the equation
[tex]-\frac{1}{3}(2.7d+1.8)=-0.9d-0.6[/tex]now let's equate both sides
[tex]\begin{gathered} -0.9-0.6=xd-0.6 \\ \text{comparing both sides} \\ x=-0.9 \end{gathered}[/tex]the missing coeffiecient to make both expression equal is -0.9
