Question

Use slopes to determine if the lines 4x−7y=9 and 7x+4y=5 are perpendicular.

Answer 1

Perpendicular.

Explanation:

4x - 7y = 9 ---> 7y = 4x - 9 ---> y = 4/7 x - 9/7, slope= 4/7

7x + 4y = 5 ---> 4y = - 7x + 5 ---> y = - 7/4 x + 5/4, slope = - 7/4

lopes are negative-reciprocal , so these lines are perpendicular.