Answer: She attended to 7 weekday games.
Explanation:
Let's denote our variables as:
Wd = number of weekday games that she attended.
We = number of weekend games that she attended.
We know that in total, she attended to 23 games, so we have:
Wd + We = 23.
"If Ariel attended nine more weekend games than weekday games" can be written as:
We = Wd + 9.
Then we have the system of equations:
Wd + We = 23.
We = Wd + 9.
The first step would be to replace the second equation into the first one, as:
Wd + We = 23.
Wd + (Wd + 9) = 23
Now we can solve this for Wd.
2*Wd + 9 = 23
2*Wd = 23 - 9 = 14
Wd = 14/2 = 7
She attended to 7 weekday games.
And:
We + 7 = 23
We = 23 - 7 = 16
She attended at 16 weekend games.