[tex]-\dfrac12x+3=-x+7[/tex]
Add -3 to both sides:
[tex]-\dfrac12x+3-3=-x+7-3[/tex]
[tex]-\dfrac12x=-x+4[/tex]
Multiply both sides by -2:
[tex]-2\times\left(-\dfrac12\right)x=-2(-x+4)[/tex]
[tex]x=-2(-x+4)[/tex]
On the right hand side, distribute the -2:
[tex]x=2x-8[/tex]
Add -2x to both sides:
[tex]x-2x=2x-2x-8[/tex]
[tex]-x=-8[/tex]
Divide by -1:
[tex]\dfrac{-x}{-1}=\dfrac{-8}{-1}[/tex]
[tex]x=8[/tex]
(and not [tex]x=-8[/tex], unless the original equation wasn't correctly written/interpreted?)
