Answer:
15 wins and 6 draws
Explanation:
Here I will use indifferently the words tie and draw.
If the team played 30 and lost 9 it must have won or tied 21 games. Lets call w a win and t a tie we have that:
w + t = 21 [equation 1]
The 47 points it gained are due to either victories, that give 3 p, or ties, that give 1 p. So, the total 47 points can be expressed as:
3w + t = 47 [equation 2]
Take now equation 1 and get the value of w in function of t (or t in function of w):
w = 21 - t
Now replace it in equation t:
3(21-t) + t = 47
63 - 3t + t = 47
63 -2t = 47
subtract 63 in both sides:
-2t = -16
t = -16/-2
t = 8
So, the team draws 8 games. Lets replace it in equation 1 to get w:
w + 6 = 21
Subtract 6 in both sides:
w = 15
And the team won 15 games.
Solutions: 15 wins and 6 draws