The discriminant is the part of the quadratic formula under the
square root, b²-4ac.
If it's positive, there are two real solutions
If it's zero, there is 1 real solution
If it's negative, there are no real solutions
(but there are two imaginary solutions)
x² - 16x + 4 = 0
Always first compare an equation like this to this:
ax² + bx + c = 0
There is an understood 1 before th x², so think of your equation as
1x² - 16x + 4 = 0
Then a = 1, b = -16 and c = 4
The formula for the discriminant is
D = b² - 4ac
Substitute in the discriminant formula:
D = (-16)² - 4(1)(4)
D = 256 - 16
D = 240. That's positive so there are two real solutions.
Edwin
