Question

The components of a vector V can be written (Vx, Vy, Vz).
What are the components and length of a vector which is the sum of the two vectors, V1 and V2, whose components are (5.0, 1.3, -15.0) and (2.3, -4.7, -1.0)?

Answer 1

Add the components for the vector sum
You get (7.3, -3.4, -16.0)

The length of any vector is the square root of the sum of the squares of the components.

Answer 2

Vx = 5.0+2.3
Vy = 1.3-4.7
Vz = -16

length = sqrt (Vx^2+Vy^2+Vz^2)