Question 1126724
7. m1 = 2 an m2 = 1/2       
Neither<br>

8. m1 = 2 and m2 = - 1/2
Perpendicular (when m1= -1 / m2,  the lines are perpendicular) <br>
 
9. m1 = 2 and m2 = -2
Neither<br>

10. m1 = 2 and m2 = 4/2
Parallel  (when m1 = m2, the lines are parallel) <br>
 
11. m1 = 0 and m2 = undefined 
Perpendicular (this is a special case, m2 undefined means that line is vertical, and m1=0 indicates that line is horizontal) <br>