Lesson 9-6 Quadratic Formula & Discriminant

What is the quadratic formula?

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

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

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

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

Tags

CCSS.HSA.REI.B.4

What is the formula for the discriminant of a quadratic equation?

•  $\frac{-b}{2a}$  

•  $b^2-4ac$  

•  $ax^2+bx+c$  

•  $\frac{-b\pm\sqrt{b^2-4ac}}{2a}$  

What does the discriminant tell us?

• The maximum or minimum

• The y-intercept

• The number of solutions

• The axis of symmetry

If the discriminant is positive, then the solution will be

• one real solution

• two real solutions

• no real solutions

• one imaginary solution

Tags

CCSS.HSA.REI.B.4

If the discriminant is negative, you will have....

• two real solutions

• two irrational solutions

• no solution

• one solution

Tags

CCSS.HSA.REI.B.4

If the discriminant is equal to 0, how many solutions are there?

• No solutions

• 1 Solution

• 2 Solutions

• Infinite solutions

Tags

CCSS.HSA.REI.B.4

If the discriminant is equal to 4, how many solutions are there?

• No Solutions

• 1 Solution

• 2 Solutions

• Infinite Solutions

Tags

CCSS.HSA.REI.B.4

If the discriminant is equal to -2, how many solutions are there?

• No Solutions

• 1 Solution

• 2 Solutions

• Infinite Solutions

Tags

CCSS.HSA.REI.B.4

Which graph has a discriminant = 0?

• None of them
• Red
• Blue
• Green

Tags

CCSS.HSA.REI.B.4

CCSS.HSA.REI.D.11

Is the discriminant for this function positive, negative, or zero?

• Positive

• Negative

• Zero

• Not enough information