Quadratic Formula Applications

Either use quadratic formula or your calculator (2nd trace, zero, left guess, right guess, guess) to find out when this object hits the ground: 
h(t) = -16t² + 20t + 6

• -.25 seconds 

• 1.5 seconds 

• 6 seconds 

• .5 seconds 

An object flies through the air and follows a parabolic path. What does the y-axis represent?

• time 

• height from the ground 

• horizontal distance 

• money 

If the graph shows price vs profit, at which prices would you "break even" (neither lose or gain money)? 

• 10 and 60 

• 20 and 50 

• 30 and 40 

• 35

Which one are we looking for? Jack wants to know how high the soccer ball will get if he kicks it straight up in the air.

• x at vertex

• y at vertex

• positive zero

Which one are we looking for?

Sally threw a ball in the air. Sally’s friend wanted to find out how high the ball got given that it took 1 second to get to its highest point.

• x at vertex

• y at vertex

• positive zero

Which one are we looking for?
Ray found the maximum height of a basketball thrown from half court to be 21 feet and wants to know how long it took to get there.

• x at vertex

• y at vertex

• positive zero

How do I find the highest point?

(choose all that apply)

• Use the axis of symmetry formula.

• Find the x-value of the maximum of the function.

• Find the y-value of the maximum of the function.

• Find the positive zero of the function.

• Use the axis of symmetry formula, plug back into equation.

Which one are we looking for?

Nancy is trying to find how many seconds it will take a golf ball to get to its highest point after being hit on the golf course.

• x at vertex

• y at vertex

• positive zero

Solve for x:

3x² - 6x - 6 = 0

• x = -.73, 2.73

• x = 3, -6

• x = 4.8, 2.7

• Undefined

If the discriminant of the quadratic equation is equal to 0, how many real solutions are there?

• None

• One

• Two

• Infinite