Posted by **Anonymous** on Saturday, February 19, 2011 at 6:45pm.

(x=1 is the day tickets go on sale)

Tickets= -0.2x^2+12x+11

1) Use the quadratic equation to determine the last day that tickets will be sold.

Note. Write your answer in terms of the number of days after ticket sales begin.

2) Will tickets peak or be at a low during the middle of the sale? How do you know?

For this problem I already solved for the peak value that will occur on day 30 by using the formula -b/(2a).

When x is 30 the maximum value of y is 191. right?

To find the last day the tickets could be on sale I need to factor to find the two values in which the value of x is 0. (or use the quadratic formula) I'm not sure I did this right because it doesn't look right. can someone help and verify if I am on the right track?

- Algebra -
**Helper**, Saturday, February 19, 2011 at 8:10pm
-0.2x^2+12x+11

When x = 30, y = 191, so yes, you are correct.

Solve this equation by completing the square,

-0.2x^2+12x+11

Divide both sides by -0.2

x^2 - 60x - 55 = 0

x^2 - 60x = 55

x^2 - 60x + 900 = 55 + 900

(x - 30)^2 = 955

+ - (x - 30) = (sqrt(955))

+ x - 30 = 30.9031

x = 60.9031

- x + 30 = 30.9031

- x = 0.9031

x = -0.9031

## Answer this Question

## Related Questions

- math - A)Use the quadratic equation: Tickets=-0.2^2+12x+11, to determine the ...
- Algebra - x=1 is the day tickets go on sale. Tickets=-0.2x^2+12x+11 use the ...
- Alegebra - x=1 is the day tickets go on sale. Tickets=-0.2x^2+12x+11 use the ...
- Quadratic equations - I need to provide a quadratic equation that models the ...
- Algebra - Given the equation: -0.2xsqrd+12x+11 Use the quadratic equation to ...
- Quadratic equations - OK. I think I have my head around most of this but for one...
- Mat/117 App F - 1. Suppose you are an event coordinator for a large performance ...
- Algebra Word problem - Suppose you are an event coordinator for a large ...
- quadratic equation - suppose you are an event corrdinator for a large ...
- math - suppose you are an event corrdinator for a large performance theater. One...

More Related Questions