Answer:
a. a = -12
b. a = 27
Step-by-step explanation:
a. Two lines that are parallel have the same slope, making the slopes equal ot each other:
[tex]-\frac{3}{2} =\frac{18}{a}[/tex]
We can cross multiply and solve for a:
[tex]-3a = 36\\a = -12[/tex]
b. Two lines that are perpendicular have the negative reciprocal of each other. This means that you would flip the fraction and multiply by a negative as shown below:
[tex]-\frac{3}{2} --> \frac{2}{3}[/tex]
This would be the slope of the other line, so we can write:
[tex]\frac{2}{3} = \frac{18}{a}[/tex]
as both expressions express the slope of the same line. We can cross multiply and solve to get:
[tex]2a = 54\\a = 27[/tex]
