find the slopes of each
for
ax+by=c
slope=-a/b
for y=mx+b
m=slope
the slopes of paralell lines are equal
the slopes of perpendicular lines, when multiplied together, yeild -1
so
-1x+4y=20
sloope=-(-1)/4=1/4
check each
y=-4x-3
-4 times 1/4=-1
perpendicular
y=-1/4x+6
-1/4 and 1/4
neither
-1x+4y=8
-(-1)/4=1/4
1/4=1/4
paralell
4x+1y=-1
-4/1=-4
-4 times 1/4=-1
perpendicular
y=−4x−3: perpendicular
y=−14x+6: neither
−x+4y=8: paralell
4x+y=−1: perpendicular
