B) No, that does not prove the conjecture. Use your formula for the tangent of a sum of angles.

A)REALLY BIG HINT:

On a set of x-y coordinate axes, spot the following points:

A: (1,0)

B: (1,1)

C: (-1,3)

D: (-10,0)

Draw Line segments from the Origin (O) to each of these four points.

What are the lengths of these line segments?

Draw a line segment between A and B

Draw a line segment between B and C

Draw a line segment between C and D

What are the lengths of these line segments?

What can you say about the measure of ?

What can you say about the three angles at the origin? What are their tangents?