math
posted by John .
Find the angle formed when [3, 4] and [−5, 12] are placed tailtotail, then find components for the vector projection that results when [3, 4] is projected onto [−5, 12]

in your notes or in your textbook, I am sure you will find the following two formulas
for any two vectors a and b
1. a•b = abcosØ where Ø is the angle between them
2. The projection of a onto b is a•b/b
sub in the values and go for it.