[tex]k:~~y=-3x+5\\\\l:~~y=ax+b ~~szukana~~prosta\\\\k~~\perp ~~l~~\Leftrightarrow ~~-3\cdot a = -1 ~~\Rightarrow ~~a=\dfrac{1}{3} \\\\l:~~y=\dfrac{1}{3} x+b~~\land ~~P\in l ~~\land ~~P=(3,2)\\\\\dfrac{1}{3} \cdot 3 + b=2\\\\1+b=2\\\\b=2-1\\\\b=1\\\\l:~~y=\dfrac{1}{3} x+1\\\\Odp:~~Szukana~~prosta ~~ to~~y=\dfrac{1}{3} x+1[/tex]
