In an equation in the form:
y=mx+b
Where m is the slope, if 2 lines have the same slope, they are parallel:
To be perpendicular, they need to have negative recipr
a.
y =2x
6x=3y+5(solve for y)
-3y=-6x+5
y= (-6x+5)/-3
y= 2x-5/3
Slope =2
PARALLEL
b.
2x-5y=10
-5y=-2x+10
y = (-2x+10)/-5
y= 2/5x-2
10x+4y=20
4y=20-10x
y= (-10x+20)/4
y= -5/2x+5
Slopes : 2/5 ≠ -5/2