15.
I had x before the movie.
x - 13.50 = 26.50
Add 13.50 to both sides of the equation:
x = 40
I had $40 before the movie.
16.
The original balance was x.
x - 161.15 = 423.28
Add 161.15 to both sides:
x = 584.43
The previous balance was $584.43
4x-5y=3
4x-5(10)=3
4x-50=3
+50 +50
4x=53
/4 /4
x=53/4
5 km = 5000 M = 500000 Cm
50,000 is the nearest ten thousand.