If x is greater than 0, then it will remain on the right side, on quadrants I and IV. If y is less than 0, then it will be on the bottom, so we are left with quadrant IV:
x is greater than 0, so all possible values are positive
y is less than 0, so all possible values are negative
You can find the number of boys and girls by dividing the total, so there are a total of 20 boys and 30 girls in the choir of 50. The ratio 2 boys : 3 girls means we can divide the chorus into groups.