Since 1/3 can't be turned into a decimal, change .5 into 1/2. In order to subtract, the fractions need a common denominator. The least common denominator is 6. So 1/3 turns into 2/6, and 1/2 turns into 3/6. Now you need to take 9 3/6 minus 6 2/6. The answer is 3 1/6 gallons of water.
Amount of money received when x tickets are sold=$Y
Number of tickets sold=X
Slope of line= 
And , y- intercept = 8
Equation of line having slope m and y-intercept c is given by,
y = m x + c,
Expressing the above statement in terms of linear equation in two variable i.e a line is
Y =
X + 8
I can help you, as long as it's something I've already learned so as long as it anything less than stats. I'll pm you.