[tex]Mamy ~~dwie ~~proste:\\\\y=a_{1} x+b_{1} ~~oraz ~~y=a_{2} x+b_{2}\\\\sa~~one~~rownolegle~~jesli~~ich~~wspolczynniki~~kierunkowe~~sa~~rowne:\\\\a_{1} =a_{2} \\\\zad.b\\\\k:~~y=3x+a\\\\m:~~y=4+(4+a)x\\\\k \Vert m~~\Leftrightarrow ~~4+a=3~~\Rightarrow ~~a=-1\\\\zad.c\\\\k:~~y=(1-a)x+\\\\m:~~y=(2a-5)x-9\\\\k \Vert m~~\Leftrightarrow ~~2a-5=1-a~~\Rightarrow ~~a=2\\\\zad.d\\\\k:~~y=0\cdot x + 8\\\\m:~~y=(a-10)x+7\\\\k \Vert m~~\Leftrightarrow ~~a-10=~~\Rightarrrow ~~a=10[/tex]
