For x = the number of $1 decreases, the number of tickets sold is
q = 1700 +200x
And the revenue per ticket is
25-x
So, the total revenue is
r(x) = (25 -x)(1700 +200x)
We want to find x such that this amount is 55,000, so we can use the equation
55000 = (25-x)(1700+200x)
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A graphing calculator shows two solutions to this equation.