What is the equation of a line that passes through (1,2) and is perpendicular to the given line?
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The given line passes through (0,10) and (2,0), so its slope is
[tex]\frac{10-0}{0-2}=-5[/tex]
Since perpendicular lines have negative reciprocal slopes, the slope of the line we want to find is 1/5.
Substituting into point-slope form,
[tex]y-2=\frac{1}{5}(x-1)\\\\y-2=\frac{1}{5}x-\frac{1}{5}\\\\\boxed{y=\frac{1}{5}x+\frac{9}{5}}[/tex]