Explanation:
a) given slope=m1=a/3
slope of parallel line=m2=5/6
parallel lines have equal slopes:
m1=m2
a/3=5/6
a=5/6×3
a=5/2
b) m1=a/3
m2=-2/9
lines are parallel:
m1=m2
a/3=-2/9
a=-2/9×3
a=-2/3
c)m1=a/3
m2=6
Slopes are perpendicular:
m1×m2=-1
a/3×6=-1
a×2=-1
a=-1/2
d)m1=a/3
m2=6/7
lines are perpendicular:
m1×m2=-1
a/3×6/7=-1
a×2/7=-1
a=-7/2
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