I need help to understand this solved problem how they got the answer ?

explain steps and digram in the picture and why they used tan inverse ?

A proton moving in a magnetic field with velocity 105 m/s in the + x direction experiences force 1.20 x 10:16 Newtons in the + z direction. A second proton with velocity 2 x 105 m/s in the + y direction experiences force 4.16 x 10-16 Newtons in the - z direction. Solve for the magnitude and direction of the magnetic field. 8 = 27: 9240 +x V = 10 m/s fxdirection - 2 = 4 1 16 * 1076 ( - 2) F.= 1.2 4 10 ( 427 2 _FZ F , = qV 2 2 F =q VB, 4, 16 * 10" = 9/2x106)By 1,2X 10- - 16 -61. 60 * 10- 19 ) B = 1 3 * 10 ( + X ) 1213x1072+( 7. 5X104) tan 7 5 X to = 1,5x10 -35 9