Final answer:
To find the magnitude and direction of F3 in polar format, convert the forces to their component form and use trigonometric relationships.
Step-by-step explanation:
To find the magnitude and direction of F3 in polar format, we first need to convert the given forces into their component form. Using the given information, we have:
F1 = (200 N, 50 degrees) and F2 = (400 N, 85+X degrees).
Now, we can use the trigonometric relationships to find the x and y components of F3, and then convert them back to polar form to determine its magnitude and direction.