parallel, neither , or perpendicular

4x+3y=10
3x-4y=8

4x+3y=10

3x-4y=8

put these in the form
y = m x + b
where m is the slope
and b is the y axis intercept (y when x = 0)

3 y = -4x+10 --> y = (-4/3)x + 10/3

4 y = 3x-8 --> y = (3/4) x -2

Note that the second slope = -1/the first slope
so
The two lines are perpendicular.