A: 50x+0.60(200)=1620
B: It's kinda up to you to write what you've learned about the equality property but I'll give you the steps.
50x+0.60(200)=1620
50x+120= 1620
50x=1620-120
50x=1500
x=1500/50
x=30
C= Donna spent 30 days on her trip.
Check:
50(30)+0.60(200)=1620
50(30)+0.60(200)=1620
1500+120=1620
1620=1620
