Question

10.

Answer 1

Answer:    The answer is either letter A or letter D

0

Hint 1: Find the direction cosines of AB and BC. Then take their dot product. This will give the cosine of the angle between AB and BC.

Hint 2: The Direction Cosines of PQ, P(x1,y1,z1) and Q(x2,y2,z2), are (±x2−x1(x2−x1)2+(y2−y1)2+(z2−z1)2√,±y2−y1(x2−x1)2+(y2−y1)2+(z2−z1)2√,±z2−z1(x2−x1)2+(y2−y1)2+(z2−z1)2√)

Edit: The Dot Product works iff the lines intersect.

B is the intersect point , doesn't matter if it's in 2D or 3D – Ali Apr 28 '18 at 5:52

0

Lines in dimension three do not have to intersect. We find their direction vectors to see if they are parallel.

Note that

AB→=<x2−x1,y2−y1,z2−z1>

and

BC→=<x3−x2,y3−y2,z3−z2>

These vectors are the direction vectors are your lines.

The dot product

AB→.BC→

along with the norms of these vectors determine the angle between the lines if they intersect at all.

cosθ=AB→.BC→||AB||.||BC||

Step-by-step explanation:    This is for the picture

Center:  (0, 0)

Width:  10

Angle:  0 rad

Height:  6.8

Opacity:  1

Answer 2

Answer:

The slope of the line 3.

Step-by-step explanation:

The line is going through 3.  Although it is not -3, because if the line is sloping upward from left to right, then the slope is positive (+). If the line is sloping downward from left to right, the slope is negative (-).