Why does this current angle change when solving for sending-end power factor?

[nimnoo]

(I think this problem has a typo; 0.8 lagging power factor should be 0.85 lagging.) When the solution starts solving for V_S, the sending-end voltage, 5.11 degrees is subtracted from the current angle. Is that the angle from V_R, the receiving-end voltage? If so, how do you solve for that angle?

 

[jd5191]

You're right, there's a typo, but they still got the right answer, their typo is on one line ...

 

[nimnoo]

Ha, thank you! I had blinders on staring at this too long.