1. The problem statement, all variables and given/known data If vector a is added to vector b = 7.4i + 7.7j, the result is a vector in the positive direction of the y axis, with a magnitude equal to that of vector b. What is the magnitude of vector a? 2. Relevant equations 3. The attempt at a solution (Is the vector in the positive direction of the y-axis same positive direction of x-axis? cosθ=u.v/||u|| ||v|| ||ab||=5=||b||.