Quadratic Formula & Discriminant Review

What is the quadratic formula?

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

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

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

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

Solutions of a quadratic equation are also called

• roots

• x-intercepts

• zeros

• All of the above

Identify a, b and c in the quadratic equation: $2x^2-3x-5=0$   

• a = 2 , b = 3, c = -5

• a = 2, b = -3, c = 5

• a = 2, b = -3, c = -5

• a = -2, b = 3, c = 5

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

• None

• One

• Two

• Infinite

If the discriminant of the quadratic equation is equal to 4, how many real solutions are there?

• None

• One

• Two

• Infinite

If the discriminant is equal to -2, 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

____________

For the function above, determine whether the discriminant is positive, negative, or zero.

• Positive

• Negative

• Zero