Answer:
a) Vf = at + Vi
b) 10 m/s
Explanation:
Part A:
first bring the t to the other side, when doing this the t will become a numerator: at= Vf-Vi
now bring the Vi over to the other side and flip the sign: at + Vi = Vf
this can be rewritten as Vf = at + Vi
Part B:
substitute the numbers: Vf = (2)(3) + 4
solve to get: Vf = 10 m/s