Determine which of the following equations are perpendicular to each other. I. y=-3x+2
II. -3x+2y=1
III. x+3y=1
IV. y+1/3x+9
A. I and III
B. I and IV
C. II and IV
D. None of these equations are perpendicular.
Write each equation in y = mx + b form so that you can compare the slopes. Perpendicular slopes are opposite reciprocals. For example: 2/3 and - 3/2; 4/5 and -5/4; 1/2 and -2
I. y = -3x + 2 m = -3 II. y = 3/2 x + 1/2 m = 3/2 III. y = - 1/3x + 1/3 m = -1/3 IV. y = 1/3x + 9 m = 1/3 (I assuming this one had a typo in it since there is no equal sign.) LETTER B is the answer I & IV
