-108x(x-3) I’m pretty sure
<h2>f = -5</h2><h3></h3><h3>f(x) = 4x - 9</h3><h3>Add 9 to both sides</h3><h3>f(x) + 9 = 4x</h3><h3>Divide x from both sides</h3><h3>f + 9 = 4</h3><h3>Subtract 9 from both sides</h3><h3>f = -5</h3><h3></h3><h3><em>Please let me know if I am wrong.</em></h3>
We assume all money is spent on new lighting. Since they currently have $160 and need $400 we can subtract what they currently have from what they need.
$400-$160 = $240
Since we know the price of the ticket and now know they need $240 we can divide our $240 with the price of each ticket ($3)
$240/$3 = 80
So the drama club has to sell 80 more tickets in order to afford new lighting
