Answer :
[tex]General\ equation\ for\ line\ in\ slope\ intercept\ form:\\\\y=ax+b\\\\
a-\ slope\\a=-2\\\\y=-2x+b\\\\Substitute\ point\ (6,-8)\\\\
-8=-2*6+b\\
-8=-12+b\ \ \ |Add\ 12\\
4=b\\\\
Equation\ of\ line:\\
y=-2x+4.[/tex]