On a spacecraft two engines fire for a time of 590 s one

Question

Problem: On a spacecraft two engines fire for a time of 590 s. One gives the craft an acceleration in the x direction of ax = 5.35 m/s², while the other produces an acceleration in the y direction of ay = 7.59 m/s². At the end of the firing period, the craft has velocity components of vx = 3741 m/s and vy = 4815 m/s.

Part A: Calculate the magnitude of the initial velocity.

Please show clear work for points. Thanks!