Answer:
-1
Explanation:
The slope-intercept form of the equation of a line is:
[tex]\begin{gathered} y=mx+b \\ m=\text{slope} \end{gathered}[/tex]Given the line:
[tex]\begin{gathered} 2x-2y=20 \\ 2(x-y)=20 \\ x-y=10 \\ y=x-10 \end{gathered}[/tex]The slope of the given line, m=1
Two lines are perpendicular if the product of their slopes is -1.
Let the slope of the line perpendicular the equation = n.
[tex]\begin{gathered} n\times m=-1 \\ n\times1=-1 \\ n=-1 \end{gathered}[/tex]The slope of a line perpendicular to the equation is -1.
