parallel lines, slope is the same so
1) 3x+8y = 12
8y = -3x + 12
y = -3/8(x) + 3/2, slope = -3/8
slope of a line that is parallel = -3/8
2)5x+4y = 5
4y = -5x + 5
y = -5/4(x) + 5/4; slope is -5/4
slope of a line that is parallel = -5/4
--------------------
perpendicular, slope is opposite and reciprocal
3)
3x+8y = 11
8y = -3x + 11
y = -3/8(x) + 11/8. slope = -3/8
slope of perpendicular line = 8/3
4)
x = -7, slope is undefined
so slope of perpendicular line is 0
5)
3x+2y = 12
2y = -3x + 12
y = -3/2(x) + 6 ; slope = -3/2
5x - 6y = 8
6y = 4x - 8
y = 2/3(x) - 4/3; slope is 2/3
slope is opposite and reciprocal, so the equals are perpendicular
6)
3x + y = 5
y = -3x + 5; slope = -3
6x + 2y = -15
2y = -6x - 15
y = -3x - 7.5; slope = -3
both have slope = -3 so equations are parallel