Answer:
x = 21 ½
or
x = 21.5
Step-by-step explanation:
x = number of games.
6x = 6 games.
Since billy scores 129 points in these 6 games, that would mean we can set up this equation:
6x = 129.
Now divide both sides by 6 to get x alone.
x = 21 ½
or
x = 21.5