So far, two-thirds of the seniors brought prom tickets. If they need a minimum of 250 people to attend in order to keep the venue, how many students must be in the senior class to ensure they sold enough tickets?

Step-by-step explanation:

we have

For x=2, y=1

substitute

-----> equation A

Remember that

If the function has a relative minimum in (2,1), then the first derivative of the function must be equal to zero when x=2

The first derivative is equal to

so

----> equation B

Solve the system of equations A and B by substitution

Substitute equation B in equation A

solve for b

Find the value of b

---->

The quadratic equation is