I know how to tell when the planes are parallel, but not perpendicular, if anyone could help out.

Determine whether the planes are perpendicular:

3x - y + z - 4 = 0;

x + 2z = -1

Another one,

Determine whether the line and plane are perpendicular:

x = -2 -4t

y = 3 - 2t

z = 1 + 2t

2x + y - z = 5

Any help is greatly appreciated!