Unit 4 QF, discriminant, projectile motion

What is the quadratic formula?

• $x=\frac{b-\sqrt{\left(b\right)^2-4\left(a\right)\left(c\right)}}{2\left(a\right)}$

• $x=\frac{-\left(b\right)\pm\sqrt{\left(b\right)^2-4\left(a\right)\left(c\right)}}{2\left(a\right)}$

• $x=\frac{\left(b\right)\pm\sqrt{\left(b\right)^2-4\left(a\right)\left(c\right)}}{2a}$

• $x=-\left(b\right)\pm\sqrt{b\pm4\left(a\right)\left(c\right)}$

What is the most efficient method would you use to solve $x^2-16=0$   

• Factoring Method

• Completing the Square Method

• Quadratic Formula

• Square Root Method

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

• None

• One

• Two

• Infinite

Use the quadratic formula to find the solutions for

y = -x² - 5x + 12

• No Real Solution

• 
• 
• 

What is the value of the discriminant of -2x² − x − 1 = 0

• 76

• -7

• 9

• none of these

What is the value of the discriminant of 6x² − 2x − 3 = 0

• 76

• 29

• 68

• none of these

The height of an object thrown into the air can be modeled by the formula h(t) = -16t² + 70t + 95, where h(t) is in feet after t seconds.
What is the height of the object after 5 seconds?

• 95 feet
• 45 feet
• 70 feet
• 171.56 feet

A ball is thrown into the air with an upward velocity of 100 ft/s. Its height, h, after t seconds is given by the function
 h = -16t² + 64t + 960.
When did the ball hit the ground?

• 10 seconds
• 2 seconds
• 5 seconds
• 7 seconds

A ball is thrown into the air with an initial velocity of 100 ft/s. Its height, h, after t seconds is given by the function

h = -16t² + 100t + 5.

When did the ball hit the ground?

• 6.300 seconds

• 11.251 seconds

• 5.369 seconds

• 7.458 seconds

Which algebraic method of solving quadratics would be the quickest for the following quadratic? x² -121 = 0

• Factoring

• Square Root

• Completing the Square

• Quadratic Formula