# pre-algebra help

posted by
**carol**
.

Determine which two equations represent perpendicular lines.

(a) y = 3/10x -3

(b) y= - 10/3x -3

(c) y = -1/5x + 3/10

(d) y = 1/5x – 3/10

Equations (a) and (b) are perpendicular t one another, because the product of the slopes is -1.