tlong dibntu dgn cranya

m = -a/b
m = -6/-4
m = 3/2
m1 = m2
i) m = 1 ½
m = 3/2 => sejajar
ii) m = -a/b
m = -3/2 => tdk sejajar
iii) m = -a/b
m = -(-9)/6
m = 9/6
m = 3/2 => sejajar
iv) m = -2/3 => tdk sejajar
jadi jawabannya b (i dan iii)