Geometric Methods for Adding Vectors: Are You Doing It Right?

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Qube
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Represent the below vector relationship geometrically, illustrating two different ways of adding vectors.

Vector a - vector b = vector c.

I know the above relationship can also be expressed as:

Vector a + (-vector b) = vector c.

In other words, we flip the direction of vector b and add as usual.

Attached are two pictures of me adding two *arbitrary* vectors a and b (vectors a and b change in the two attached photos).

In the first picture, I use the parallelogram rule. In the second picture, I use another method to add the arbitrary vectors a and b.

Did I add the two vectors together correctly?
Chalkboard diagram with a parallelogram of vectors: vector -a and vector b share a tail, with dashed sides completing the parallelogram, and vector c drawn as the diagonal from the tail to the opposite corner; labels a (circled at top left), -a, b and c.

Handwritten chalk diagram on a blackboard of three vectors forming a triangle: vector a and vector b drawn tail to tail, with vector c drawn from the tip of a back to the tip of b.
 
Qube said:
Represent the below vector relationship geometrically, illustrating two different ways of adding vectors.

Vector a - vector b = vector c.

I know the above relationship can also be expressed as:

Vector a + (-vector b) = vector c.

In other words, we flip the direction of vector b and add as usual.

Attached are two pictures of me adding two *arbitrary* vectors a and b (vectors a and b change in the two attached photos).

In the first picture, I use the parallelogram rule. In the second picture, I use another method to add the arbitrary vectors a and b.

Did I add the two vectors together correctly?
Your problem statement has the "-" sign with vector b, but your drawing has the "-" sign on vector a instead. Other than that, you have the right idea.