1. Unit 7 Day 4
the Quadratic Formula

2. We can use the quadratic formula to solve quadratic equations in the form:
x =

3. Example 1:
2x2 + 6x + 1 = 0

4. Examples
2. x2 – 4x + 3 = x2 + 2x – 1 = 0 4. x2 = 3x – x2 – 2x = 3

5. The discriminant determines the type and number of solutions.

6. If the discriminant is POSITIVE, there are 2 REAL solutions.
If the discriminant is ZERO, there is 1 REAL solution
If the discriminant is NEGATIVE, there are 2 IMAGINARY solutions.

7. Determine the type of solutions by using the discriminant:
x2 – 22x = - 121
x2 – x – 1 = 1
x2 = - 4
7x2 – 4x = 0
9x2 + 12x = -4