Question

Renee and Zelda are at position A. At the same time, they start moving toward their destination B at time t = 0. Renee's speed is given by the function v A = 4 + 3t, and Zelda's speed is given by the function v B = 5 + 2t, where t is the number of seconds and v is meters/second. What is their total speed at t = 3 seconds?