Question

determine whether AB and AC are parallel,perpendicular,or neither.A(9,-3) , B(9,4), C(-2,10), D(-2,6)

Answer 1

We first determine the value of AB & CD:

AB (0, 7)

CD (0, -4)

We will calculate first if they are perpendicular:

`(0,7)\cdot(0,-4)=0\cdot0+(7)(-4)=-28\\e0`

From this, we know AB and CD are not perpendicular.

Now, in order to know if they are parallel, we will do as follows:

`(0,7)x=(0,-4)`

From this, we will have:

`(0,7x)=(0,-4)\Rightarrow7x=-4\Rightarrow x=-(4)/(7)`

From this we have that they are multiple of each other, therefore they are parallel.